Were they portal guys or "transfers"? Nevertheless, your point about losing guys to the portal stands.
Epps got far more PT as the season went on, and after Clark left, so I am skeptical that his average mpg is a good reading of his PT at the end of the season.
Umm, I'm not sure how to answer that first question. There are very few guys left who were able to 'transfer' before the portal existed - if any.
Yes, Epps got more PT when Clark left - of course he did. But when Clark was available, he played more than Epps. It's not like Skyy Clark didn't play, he was a day one starter.
EDIT: Looking at it now, Epps was getting 24 mpg before Skyy Clark left, and got 28mpg after he left (and before Jayden got hurt). So not a giant leap in minutes, but not a tiny one either.