The problem is that Coordination is nostr only, so it offers questionable decentralization, just like Mixin Safe: A Convenient and Decentralized Multisig, which was hacked several months ago.
You can't really compare Nostr with Mixin Safe that was fully centralized with data kept on cloud servers, and they use shitcoin blockchain ecosystem.
I was one of the people who reviewed Mixin Safe and straight away I said that this is unsecure system that is just waiting to be exploited.
Joinstr sounds very interesting and I think it's going to be easier to use it than joinmarket.
Anyone can be a coordinator but question is who is going to do it.
Electrum isn't advertising itself as privacy focused
So what?
You use your own node and you have privacy, you don't need electrum to tell you that.