Some years back they rebalanced the game, making creatures much more powerful, but making spells weaker. I used to play red, so Lightning Bolt was the quintessential magic card for me, but now it’s too powerful to reprint.

Creatures on the other hand, way more powerful.

But I don’t think they have a power creep problem, although admittedly I only read up on the game periodically, not play. I think they did one main rebalancing, and that’s it. It’s not like cards from a few years ago are unplayable.