True that you can't count on ANY player to stay at 1 school for 4-5 years now.
But that doesn't mean you should exploit him either (not saying playing him would).
If he is really really good, yeah, he won't even use that last year (maybe 2). But maybe he's very good, good enough to play in the NBA, but only after 4 full years of playing college ball. Those guys do exist.
Not every good or average or roll player thinks he is a start and makes unreasonable demands. I think Cal's time at UK has jaded many UK fans opinions on players, when Cal sought out players with higher than average expectations (remember the story where he told 5'8 Ulis on his visit "if you don't think you will be good enough to leave UK early to play in the NBA, don't come to Kentucky").
All that said, if he looks good enough to contribute the last 30-40% of the season, then I'm sure it's not just a Pope decision, but that he will discuss it with Hawthorne (maybe even his parents too). Put it all out on the table (e.g. I think you can help us, probably playing X-Y minutes per game. But it will cost you an extra season. I understand and won't hold it against you if you decide to stick with your RS, but I'd love to have you on the floor this last month plus.) for Hawthorne to decide.