I've advocated the formula method for years. Redditors trying to sell or promote password managers usually would just dog-pile and mass-report me when I said it.

One great feature of this, is that you can write your password down on paper or a text file too. Knowing your formula, allows you to write it down in a way that doesn't include or elude to the whole password. It's just a few letters of nonsense to anyone else. Add yearly password changing to your formula for regular rotation and you are golden.

Biggest password security failure of 2022: Using Character replacements like P@$$W0rd

Come on, its not 1990 anymore, every low quality tech college has been telling kids to do this poorly thought out trick for a decade and a half. It's easy to get around and mostly avoids adding any actual additional complexity to your password, because of it.

When you learn to crack password, the limitations become more clear. Automated tools already try silly character replacements and other cracking tools allow you to do so easily with rules and character sets. (I'm thinking of hashcat)