I'm not sure they'll be able to compete against a worse but integrated solution like MS teams long term. No doubt it's worse but the bundle is cheaper with when you're already paying for Windows and Office. Same story with G Suite.
MS and Google don't actually have to be better with their chat product, they just have to be usable and cheaper.
I use Teams in a very large org. Sometimes, the lack of integration and capability is a benefit. People don’t message me unless they actually need something.
Agree - there was a lot of talk about Slack in our org, until everyone realised we had Teams already as part of O365 and it delivers on most of the use cases you set up from Day One.
It's actually pretty good for managing discreet work streams, and even for organising personal work (kind of against the "Team" ethos, but having a channel for myself keeps my work visible and tabs keep important things to hand easily).
I have _never_ used teams. I have seen it creep up in enterprise focused orgs but I have still never used it.
As a remote worker Slack is my office, essentially, and I think it's done an amazing job at being an office for remote first companies. I can't speak for Teams.
MS and Google don't actually have to be better with their chat product, they just have to be usable and cheaper.