What SAS should've said is Giannis could end up a top-10 GOAT but he'll need another championship (probably 2-3) to break through,
i.e. a common top 12 would be a pecking order close to: Jordan, James, Jabbar, Johnson, O'Neal, Duncan, Russell*, Chamberlain*, Bird, Bryant / Curry, Hakeem.
An * by Russell and Chamberlain since some like to include '60s players (in which they could be anywhere from 4th to 10th) and others don't.
For Giannis to break into this list (even if ommitting '60s players), he'll probably need to ditch his current team for more opportune chances for titles, the same way several of the guys on that list did. At 31, he just has to make that decision since a GOAT list isn't actually tangible and is more just a competitive / ego thing rooted in barbershop talk