Different techs with different compromises.

Fedimint also exists.

I like the "simplicity" of cashu. It helps making for better custodians.

Many contexts where it makes sense.

A company could pay its employees from its mint, obfuscating who received which coins, then each employee could convert at will his tokens.

A family could run a mint for all members, maintaining a single lightning node for everyone.

Etc...

the cashu people will probably win the nostr wallet wars but it will be a sad day for my non-custodial lightning node. I guess I will just stop zapping when that day comes, I don't want to use a custodial node or run cashu just to zap.

My biggest issue with mastodon/activitypub is that your account is tied to an instance. So if the instance admin bans you you have to start over. With nostr you control your keys and social graph. This means noone can ban you and moving between relays is easy.