(bit of self-promotion)
They do have a React version on WebView2 that is (supposedly) much better, but it's only for personal accounts right now, though that could change [1].
Thankfully their internal API is fairly self-documenting, so I've been looking into creating my own Teams client if you're interested [2]. We'll see if it'll have been an effort in vain depending on how well Microsoft Teams 2.0 goes.
[1] https://www.techradar.com/news/a-new-generation-of-microsoft...