The problem is that using particularly single punctuation marks as tokens for a markup language inevitably causes text to be formatted in unexpected ways when the intent wasn't to format or pseudo-format the text (censoring words with asterisks is an amusing one), and the symbols we have on our keyboard today are so precisely because they are/were commonly used. I'm not really bothered about the "should code look like natural language" debate, but markup is supposed to be distinct from the surrounding text so that both humans and computers can easily parse them. If you have to escape characters in pretty much any text not along the lines of "what are the tags in x markup language?" your markup language is bad.
BBCode is, I maintain, serviceable, at least for the purpose it was designed for (lightly formatting forum posts). Most people don't (consciously) use markup languages at all, and otherwise very seldom, as should be self-evident. On the platforms that don't avail users of any, there is never any great outcry that they cannot be sufficiently expressive without access to e.g. italics. I don't have any attachment to the language-- I can barely remember basic tags, much less use them effectively-- but it's not exactly onerous to type out the bold tag, even if this textbox didn't have a button to automatically insert them. It seems conversely that the people really bothered by BBCode are the ones who are so attached to a certain syntax that deviance thereof is ipso facto burdensome.
The world of vaguely-nerdy people left this way of thinking behind the best part of a decade ago. People are more likely to expect asterisks to do something than to remain as asterisks as Markdown is so prevalent. Except for IRC, which exists solely to insist the nineties are still ongoing, every other communications platform OpenMW supports uses Markdown, so no one's getting tripped up by there being more Markdown and less 2004-ish syntax they don't use anywhere else. Even ignoring the slight typing-speed advantage of Markdown over BBCode, not using a weird language that's fallen out of favour makes life easier and helps keep the typing speed and thinking speed in sync as you're not having to think about typing it. For the average Internet Person in <current year>, Markdown's familiar, whereas BBCode might as well be a custom domain-specific language invented by one site, and obviously, we wouldn't implement a custom markup language on our forum.
The keys on the keyboard are mostly there because they had particular uses in the late 1800s and early 1900s in specific kinds of documents rather than natural text, and also the mid-1900s to late 1900s often because they were common in programming languages rather than natural text. They only arose as a thing that got used in informal text on the internet because they were a way of hacking in support for formatting on systems that didn't support it using the characters available, and there's no good reason to keep using them once there's sufficiently convenient support for convenient markup of some form. I write literally thousands of words of Markdown a week (maybe tens of thousands or more - I've not measured, just made a conservative estimate) and I can't remember ever needing to escape anything when not trying to explain Markdown syntax or go on the hunt for ambiguous constructs. You're making assertions about Markdown that just don't reflect reality.
Basically, you're batting for Betamax even though Super VHS levelled the playing field and also it's a long time later and people no longer bother replacing broken DVD players. The world has just moved on.
Nevertheless, as I mentioned, people rarely use markup languages here anyway, so it's hard to imagine that the vast inconvenience of typing square brackets is hampering use of the forums. What exactly is the convenience of Discord, exactly? I tried it a few years ago and would describe it as being a monstrously overdesigned and sluggish chat client whose features like uploading photos hardly justify being literally orders of magnitude worse than IRC in basic respects like responsiveness (not to mention size and resource consumption). If it really is just that everyone is using it and has it at their fingertips all the time, it wouldn't matter what forum software is being used: any self-hosted solution is going to be less convenient than just using Discord or Reddit or something.
There clearly is
some advantage to Discord over forums or IRC as people use it much more willingly. To a certain extent, it doesn't even matter what the advantages are as we're never going to convert everyone to using the forums as their primary communication method. The goal here is to try and make the forums more convenient so the things that are definitely better served by something forum-like (e.g. that we'll want to be searchable later) happen on the forums. One such step is getting rid of a markup syntax that's widely agreed to be more of a pain that we don't use anywhere else.
- Chat history sticks around so you don't have to miss stuff if you turn your computer off. If you ask someone a question while they're offline, they're still likely to see it.
- Formatting is convenient, intuitive and useful enough that people actually use it, unlike on IRC. E.g. IRC lets you change the text colour, which basically can only be used to be annoying, and requires either something client-specific to do so, or that you know how to type the non-printing 0x03 character.
- They don't target the lowest-common-denominator IRC client as everyone's roughly up-to-date, so new stuff gets added and can reliably be seen by everyone.
- No need to learn any commands to do anything - it's all available via the GUI and keyboard shortcuts, so discoverable for first-timers and convenient for regulars.
- Non-pathetic message length limit.
- Things like pictures, which most people do find worth the resource-hogging (as they're unlikely to actually notice that unless something else is competing for RAM).
- Grouping of channels so you don't need to join all fourteen public official OpenMW ones separately.
Regarding dropping the forums in favour of our subreddit, a big part of that is that Reddit's search is a load of ass. Also, the massively branching conversation structure doesn't suit planning things very well - it's harder to reach an eventual consensus if things can spin off lots of little tangents that get separated from the wider context and relevant ideas that come up in other contexts. I'm not even sure Reddit was suggested as a platform for organising things.