I think they're very fun games, that always push the hardware. But they also haven't evolved so it's pretty much the same thing as always.
I'd argue it has devolved. I'm going through the first three games in the HD Collection and the original game blows Rift Apart out of the water in level design.
Sure, Rift Apart is much larger but also more simplistic and flatter. You don't do much exploration anymore because everything is in plain view. With the original one, I was looking at my missing Gold Bolts and wondering how the hell did I only have 1/4 in Gorda City when I had explored the entire map twice. Turns out, I hadn't and there were some very well-hidden spots.
Moreover, the Metroidvania-lite style is completely gone. No more letting the player wander off only for them to hit a wall and realize they need another piece of equipment that they're not even told where it is. No more trying to figure out where X or Y gadget is located in order for you to progress. It's all hand-holdy and you basically can't get stuck in Rift Apart and there are no optional gadgets hidden in way out-of-the-way places.
Even the combat has taken a hit. It's now just a mindless shooter where you aim your gun and jump strafe and blow everything up. You don't really need to consider what weapon you're using. They mostly are the same except for different graphics when you shoot them. In the first game, even for how janky it is, you needed to be situationally aware and use the right weapon for the right job. You couldn't just charge a tank or a group of enemies with your Blaster or you'd get murked.
The platforming is also effectively non-existent.
After going through the first one, Rift Apart feels like a children's game. Nice QOL changes though and you can feel that the OG is dated in many respects but I think it's a better game than Rift Apart overall. If only they could modernize the UI, weapon wheel, and controls, it wouldn't even be a debate. Instead, we got the abomination that was 2016 because Sony were jerking around Insomniac too much and only gave them 10 months to make the game. It's miraculous that it came out as good as it did.