Basically what if passwords were just computed on demand, without having to store them, meaning no need to back up anything. No need to trust a 3rd party for your passwords.

compute_password(website_uri, username, master_password)

this is just a simplified version of a function, could add more like password length, nonce/counter etc. So example for "website.com" I have an account with "marlybob" as username my password would be for that account on that website is what ever the function returns below:

compute_password("website.com", "marlybob", "my_secure_master_password")

assuming these inputs stays the same I can always compute for my password right?

the master password could even be a 12 word seed, following the standards for cryptowallets so people could use that and will have less passwords to keep, I know wallets uses a standard for that.

Also it could not be just a hash, maybe use the hash of the inputs as seed for generating a random string.

Not sure if this is a new idea, probably not, I tried searching for password managers and all of them uses basically the same idea of generating a random password encrypting it and storing in the cloud. This just came into my mind while thinking for my bachelor thesis topic idea, I thought I could give it a shot and ask here for more info. Really curious if this could be a thing or nah.