Ohh i see this should be very much valid I guess
But I think at some higher level just abstracting wallet interaction and managing private keys in a non-custodian manner could suffice maybe have an SDK like The Thirdweb (https://portal.thirdweb.com/) Development suite (I’m in talks and partnership with the team but they’re not convinced to create support for Polkdadot I might try privy (Welcome - Privy Docs) another industry standard for smart wallets)
In all I’m very positive that it should be possible to have user managed account run in a process where they can just use simple widget interactions to sign extrinsics and without create an general programmatic wallet Onchain
Hopefully the Polkadot hub lowers this developmental barrier would love to explore solutions