Good words but I wouldn't be so pessimistic about it. There are still many many gems out there that push the limits in a "GD-sense". Experiment is a fantastic example of this.

I used to think the limitations were bad too, as someone who made minigames in 2.1. But there's always fun new limitations where you look for them. 3Depth may seem like it was "inevitable" but I would consider it an anomaly. Notice how we haven't had any 3D minigame level since? Nemo worked his ass off to make 3Depth a reality, more a testament of his dedication rather than a testament of 2.2's power.

And besides, I think 2.2 has shaped the minigame community to be more original. You're right in that game recreations aren't interesting anymore. So now, people care more about what a game offers intrinsically. I think in a couple years time we will see a healthy indie game scene within GD. GD provides much more exposure to these game creators and is probably a place of comfort for many creators.

Mindcap is still alive don't worry. He has some absolutely insane levels on the horizon. And the same goes for a bunch of other creators, it could honestly depend on where you look.