I do use passphrases, but I combine with randomness.

I memorize one random 8 character string to use with something more memorable.

Then when I need more security, or I feel that random 8 character string is no longer safe (password leak/hacked), I memorize a new 8 character string.

Then I combine them.

Then I memorize a new 8 character string and mix it in.

It's a process built up over years that ingrains into memory. Sometimes I forget the order, or if i added spaces, or did no spaces. Luckily, as long as I am sure of the discrete segments, I can remix them to recreate until it works (in a reasonable time).

My last addition was when I made the move from Lastpass to another password manager, after their endless bad news.