Reading this doc it feels like the Prettier team is saying options like tabs/spaces were only added early on to get initial adoption, if it were up to them now there would be far less options to configure at all.
The options in question are some of the more.. fancy ones, and the "history" in question is things such as cross-compatibility with ESLint. Certainly not "tab support". (And I've contributed to Prettier a great deal, FWIW)