There's a more insidious side effect to prettier related to the line length thing which I'm not sure other commenters touched upon, and the reason I avoid opinionated formatters.
Prettier will affect your diff in ways you didn't intend to.
Remove a member from a destructuring assignment that brings it below the line length limit, and suddenly your diff is +1/-5 instead of 0/-1, making it slightly more difficult for your reviewer to see what the exact difference is between those 5 lines removed and 1 line added - it's not immediately clear which member was removed.
You try to rewrite a previous commit to fix a typo using Git's interactive rebase, and now the next commits won't replay on top if it because Prettier decided to reformat an entire code block.
Another fun thing to try with prettier: add a precommit hook that runs prettier, and then try to stage partial file changes.
Prettier will affect your diff in ways you didn't intend to.
Remove a member from a destructuring assignment that brings it below the line length limit, and suddenly your diff is +1/-5 instead of 0/-1, making it slightly more difficult for your reviewer to see what the exact difference is between those 5 lines removed and 1 line added - it's not immediately clear which member was removed.
You try to rewrite a previous commit to fix a typo using Git's interactive rebase, and now the next commits won't replay on top if it because Prettier decided to reformat an entire code block.
Another fun thing to try with prettier: add a precommit hook that runs prettier, and then try to stage partial file changes.
No thanks.