That could work too but nsec.app was specifically created to have a pure web based solution without an extension, so we don't have that on the roadmap atm
They will work together. You have nsec.app on your phone and an extension on your laptop’s browser. The extension generates a key for the communication with the bunker, and you approve it once on your phone. The websites that you browse don’t need to even know that you are using a bunker. They will simply use NIP07.
I understand, but our primary use case for nsec.app is to onboard people on the web (on nostr sites) into a web-based key storage, without asking for extension install, so we're focusing on that part. If someone adds nip46 to extension I'm totally fine with that, it's just not our focus.