The big reason I'm hearing in this thread is "Denuvo and I don't trust Ubisoft." However I doubt that is the reason the mainstream audience skipped over this game. Ubisoft franchises generally sell like hotcakes, and for the most part only nerds care about DRM (like the type of person who knows what a lemmy is).

It's hard to say why it didn't sell more units. Certainly it seems their internal expectations were sky high:

similarly to the biggest Metroidvania’s in the market, with millions of units sold in a relatively short space of time

The game is good, but metroidvania is not exactly an easy market; there's some juggernauts in that genre, and they came out with a completely new and unproven concept. Apparently it sold a million units or so still, to me that's not unimpressive.

On PC, it initially launched only on Epic afaik, which certainly doesn't help. And by the time they brought it to steam it was much too late.

What I don't really get is, why disband the team? They've proven they can produce quality stuff. Just hand them some other promising projects? I suppose that's too much of a risk for a publisher like Ubisoft.