Their video offering is laughably bad but I'd bet that isn't because of electron. Otherwise I'm surprised people hate the electron app so much, on my 2014 mbp it works just fine.
But even simple stuff like "send when internet connection is back" isn't there, like what WhatsApp has.
It also doesn't load very fast for something that you'd think is mostly text. Change teams and you see the spinner a lot. Also when you've come back to WiFi it seems to take ages to get your updates.
A lot of these things seem to be "fixed" by killing the app and restarting, which is something of a smell.
Also seems to use a lot of memory. Not a huge problem on my machine, but I like elegance.
(Is there any video conferencing software that doesn't suck in some way?)