Just migrate to Discord?
I've been in Discord servers for volunteer work, and while it generally works pretty great, the system feels a lot more casual to users (e.g. with non-human profile pictures). On the other end of the spectrum, Microsoft Teams is almost too professional, and has an emotional association of being too corporate/formal for more pleasant use.
Discord is also tougher to create group conversations easily (you need to be Friends first). Though, if message history is really that important, it could be a worthwhile tradeoff.
The problem with Teams is not that it's "too professional". The problem is that there is more spacing in the interface than there is actual text. You know, the conversations - the thing it's meant to do best. Threads are a mess to follow, channels are awkward... If professional == terrible UX, then you may be right.
And let's not even talk about how unstable and unreliable it is.
I think the Teams design team tried to compromise by making the interface approachable enough for the greatest number of users. But for one reason or another (strategy to differentiate from Slack, company DNA, or other reasons), they couldn't make the interface subjectively feel more casual and less professional.
Everything from the name ("Microsoft Teams") to the logo (a bunch of people, versus the Slack logo with eyes and a mouth) is more serious, even if the team tried to soften it a bit by using less formal language in the interface.
1) That's not much of a moat for Slack. If Discord were serious about entering the enterprise market, and there's sufficient user feedback on this point, I'm sure they could adapt with a few month's work.
2) I've heard similar critique about Slack in the past as well. IMHO professional vs casual comes down to expectation and familiarity. As more youths who are accustomed to Discord enter the workforce, the casual connotation would go away.
There was a time when e-mail was considered too casual and unfit for professional communication, too.
Teams target is Corporations so it should be professional?
Microsoft has tries to make Teams "less professional" or more causal and people hate the changes. They recently changed the theme of the emoticons "Microsoft Fluent Emojis were brought to life to embrace expressiveness and play" they seem to be well received by non-professional users, or even professionals in "creative" fields, but for traditional corporate users they look terrible and are not well received at all, the feedback asking for the return of the traditional emojis has 10's of thousands of votes.
for work I want a professional platform, I want teams to be a professional tool for professionals
This Pirates of Silicon Valley scene comes to mind [0]. Teams may not be the most optimized software for formal versus informal users, but that doesn't matter because it's trying to have a broad appeal.
For example
Lync was separate from Skype... Business and Consumer
Then they got rid of Lync in favor of Skype for business... Bad
Then comes Teams, designed from the Ground up for Corporate. Dropping Skype for Business like many many wanted, a separate corporate app
Now with Win11 they are making the same mistake again with "Teams" the default app in windows 11, which is different client than the "business teams app" and at launch could not even connect to organizational teams tenants only "Microsoft" teams accounts which should be called Skype....
Skype should remain the consumer / family platform, if they want to bring "teams like" features to that great. Teams should remain a business app
A lot of very good IRC clients are available for free.
IRCCloud is a good starting point for a lot of people: excellent UI/UX, a free tier, and a very inexpensive paid tier (around 4 USD/month).
Create as many channels as you like.
I'll probably give Zulip a try before I go back to Mattermost.