Obsidian is not opensourced, I don’t like it and won’t use it to store my personal info. But it uses TS + React, and has a much larger plugin developer community, and has 100x + users than TiddlyWiki.
And what’s the problem when Tiddlywiki is in a niche market: Android app, the TidGi-Mobile app v0.7.7 - #10 by linonetwo