For a general audience, even Bitwarden doesn't pass the "grandma check". If you've used Bitwarden for a while you have probably been met with a stern warning about "KDF Iterations too low".
So I pitched the answer assuming "able to use Bitwarden" as a base level of tech savvy.
Also, seeing as I am on HN, I assumed the following:
1. Security matters, even if it comes at a slight cost in convenience
2. User can figure out their own syncing mechanism