I think max Holloway and Charles Oliveira holds most of UFC records.
Tim Elliot and Jim Miller have a lot of records too.
those things absolutely makes them notable fighters, but don't put'em in GOAT conversations.
Alex Pereira achieving champion in 3 divisions is unprecedented in UFC and is a historic feat, specially being in the 3 heaviest divisions ( MW to LHW have 20 lbs gap, and LHW to HW is like 40 lbs[250 lbs is the limit, but almost anyone reaches the limit])
I think it make him a legend, grant him a place in the HoF, and make him definitely unbeatable in accolades discussions.
But definitely not in GOAT conversations