[SushiHippie]

I'd also say Matrix, as this is where the most communities are today that are not on propietary platforms.

Although the UX is not that great, when logging in via a new device, as it takes long to do the first sync (the new syncv3 protocol is supposed to fix this but it's still in beta)

A direct Slack alternative would be mattermost.

https://github.com/mattermost/mattermost

[1oooqooq]

matrix is like IRC + obligatory GPG.

most new users keep losing identity because they have no idea they are using vector.im as their "nicksrv" of sorts and that their recovery code and password are not their session key. it's a disaster.

but having webapp and phone apps help adoption.

[Arathorn]

this is very very confused.

the key you use in Matrix to get at your historical messages /is/ your security passphrase/key (assuming you set it up).

the vector.im identity server is just a phonebook to let people discover you based on email address if you so desire.

the UX in Element is clearly a disaster, given nightmarish confusions like this. we have tried to fix it in Element X and stuff like https://github.com/matrix-org/matrix-spec-proposals/blob/and... which is looking promising

[palata]

IRC is very lightweight. Matrix feels rather at the other end of the spectrum. The IRC protocol is very simple. Matrix feels very complicated.

[1oooqooq]

real-life IRC is also extremely complicated. But you can use it incrementally.

e.g. no identity, no dcc, no figuring out the individual-and-very-particular nicksrv on each instance, etc.