Gobert is too old. 34yo.
I feel like he is going to fall off a cliff in the near to medium term future. Could be 1-2yrs or 2-3yrs. His time as a top level player is nearly over.
D White is younger and has a skill-set that should age better. He is a combo guard who can play both positions so he can shift full time to SG when he gets too slow to cover PGs defensively. He can also shoot, handle, pass, is smart. So he will age well. He could be a steady performer into his late 30s if he avoids injuries.
Gobert on the other hand is a slow footed center with a limited skill-level. He can get by on his current speed but if he loses more than he becomes a much more limited defender. He doesn't have a skill-set offensively that he can rely on as his defense gets worse. No jump-shot. Okay passing but not high level passing.
D White is the better bet.