Definitely. Would increase adoption to make a full normal ass social media app with a back end that offers that, and a way to simply download your nsec and nostr events to port it into anything else if need be. 

 Custodial nostr is wrong. The custodian can post as you and sign your stuff, it just breaks fundamental proof of authorship. Downloading your nsec doesn't give you back control. 

 That's a good point, but perhaps more clients that do everything for you except hold your keys then.