If the capabilities of the hardware have meaningfully changed, a remaster is perfectly fine.

The PS5 is a far cry better than the PS4 in every respect. The PS5 version will almost certainly be a clear upgrade. And they’re not making anyone rebuy it; you pay the $10 difference between last gen and current gen games and you get the upgrade.

The best simple metric, if the thought of asking yourself “but why?” ever occurs when you decided to do a remaster, it’s best not to do a remaster.