This is a pretty fun trope if done in a fresh way; I'm guessing the reason it's not seen that often is that, due to its very nature, a single work can explore and exhaust a lot of potential plot implications, leaving little for each subsequent work. You can't just make a time loop movie because that's just Groundhog Day and GD did about everything you can do in an "everyday scenario"; you need to change a core element to not retread it. The best examples do just that: Russian Doll (two people separately trapped in the loop), Edge of Tomorrow (action sci-fi), etc.
Terminator 2 is time travel, but isn't it specifically time travel to create a time loop? John Connor in the future sends T-800 back to the past to save Past-John Connor so that he can live to become future John Connor
There's two very different meanings of "time loop" in fiction:
- Works that feature a time loop paradox; a self-perpetuating chain of events that becomes a loop through time travel, thus every event is proximate or distal cause of every other event, including itself.
- Works where the main character's consciousness is stuck in a time loop where they re-experience a period of time over and over.
There's otherwise little thematic connection between the two meanings, and discussing both in the same thread is only going to result in two groups of people talking past each other. Given that a cursory read of the OP (and its mention of Groundhog Day and Edge of Tomorrow) makes it plenty clear they are referring to the latter, it makes sense to focus on them.
en.wikipedia.org
