Unfortunately, I don't believe the game itself tracks how many times you've been through an instance. That is data which serves no particular purpose in the game at this time and cannot be readily stored somewhere that doesn't require a massive amount of data to be searched every time you hit the toggle.

The game currently tracks:

Achievement dates (can be found on Lodestone)

Which dungeon instances you've completed

When you completed a particular quest in-game (also on Lodestone, although this one actually indicates I completed the first set of MSQ quests in the 2.0 storyline in April of 2021, rather than November of 2014. This actually appears to be the date that specific quest completion started to be tracked, as it is consistent across a number of alts I know have been around since the 2015-2017 time frame.)

I don't find many PF groups for actual leveling dungeons, as Roulette queues tend to be quick, and the content is relatively straightforward. Your suggestion of 'peak optimization' is ambiguous, and to invoke Mentor Status might be counterproductive as Mentors serve another purpose in Roulettes that shouldn't copy over to Party Finder.