I think this is a byproduct of a free and open protocol. There will be good clients and bad clients because there is no authority to stop them.
It will be incumbent on the user to do their research on whether a client is good or bad.
That being said other then word of mouth is their a rating database for Nostr clients. A place where users can give feedback so new users can pick the best clients?
nostr:npub18ams6ewn5aj2n3wt2qawzglx9mr4nzksxhvrdc4gzrecw7n5tvjqctp424 nostr:npub1l2vyh47mk2p0qlsku7hg0vn29faehy9hy34ygaclpn66ukqp3afqutajft