Actually you don't need multiple accounts, you only need one in a specific instance and can interact with other instances (My account is registered at programming.dev).

The UX is extremely wonky and I had to look it up, but you can go to the search in the top right of your instance's main page (not the "communities" subpage) and search for communities and filter by "Communities" in the top left

My impression is that it is just someone who created a community for each language they could think of.

Actually it's the /r/experienceddevs subreddit mods who created that instance. I had never heard of the subreddit before though but they had a bit above 100k subscribers

Exactly. However, since it's possible to subscribe to different instances' communities, the current situation might not be the worst? I still think the should be discussed.

Also it sucks that currently there is almost no activity across all 3 communities, i.e. single-digit posts per day

The sooner a community can be decided on, the better. /r/rust should then link to that instance in their privatization message so users who're out of the loop are not completely lost.

The first bullet point in "Project & Toolings Updates" section only has "Changelog #184" without referencing that it's about rust-analyzer. This should be changed to be more clear