Increasingly services want 2fa and other bullshit that only really plays nice with a modern smartphone. They don’t sell a lot of dumb phones fwiw. The network that your old one in the drawer ran on is shut down. The new “dumphones” are usually android phones designed for old people with poor eyesight and dexterity.
There are various ways to store the password to allow some level of management. Give half of it to a friend, write it down, make it super long.