The prog genre had its musical and commercial peak in the 70s. It had mass appeal back then. After that it got wiped over by punk and new wave.
Prog kept on going but it kept repeating itself and lost the experimental progressive nature for a very long time after that. Most of the bands were lesser copies or heavily influenced by the big six: King Crimson, Yes, ELP, old Genesis Gentle Giant and Rush. The genre, despite its name, was not progressing at all from the 80s till say the end of the 90s.
Until prog metal bands like Dream Theater came. But that made the genre more metal than prog and bands started to copy that too, again without any progression. Until the last decade or so with bands like Animals as leaders or Polyphia. That’s more math metal than prog metal though but it’s an evolution of the genre and musical progression while other bands kept repeating the big six.
I personally am not interested in copies of the big five but still listen a lot to the classic prog bands of the 70s.
Well, it's hard to keep inventing and redefining a genre. But one can easily argue that right here today, the amount of quality progressive music out there, that is blending and warping together all kinds of interesting genres (minimalist jazz, dark folk, pop, metal, etc.) and creating new musical landscapes, has never been greater.
Of course, in general, it's not going to have anywhere near the popularity of the 70s bands, but that is to be expected.
Black Midi certainly is an example of a young band, that has taken some older prog/jazz tropes (Mahavishnu Orchestra, VDGG and more) as a starting point and completely mashed it together with a bunch of modern elements into something fresh. IMO.