More likely than not in my opinion. The depth-of-field is really weird and the background looks like it was generated out of focus rather than authenticly. If you look at the parts of the photo that are in sharp detail there should be a box where things are in focus and things aren't. In this photo that box is curvey, which would be difficult to do in-camera. That suggests at least some level of digital manipulation. Whether that's just touch ups, image compression or outright ai generation I can't answer.

I would bet on it.

Yes: https://www.instagram.com/p/Cy-q5CnJsGW

It does kind of have that midjourney sheen to it...

I think so, the depth of field doesn't really make sense.