I think any client that sits at the top of the onboarding funnel it would make sense to run these things.
I am planning on building a bunch of non-bitcoiner-focused apps that will leverage this. I think this would also make a lot of sense for something like zach (npub1zac…5dy5) 's Flockstr to run (in fact, Zach came up with a username+password scheme as well but which the strings themselves compute to a key, so you would be essentially logging in to all clients directly with your nsec, which is why I think that approach is problematic, but same goal!)