I don't believe that there's any genre or sub-type of movie that is inherently, automatically bad and there's nothing that anyone could have done to make them good.
Are you sure about that?
Asylum films are intentionally bad, it's not so much a failing on the part of cast and crew but an aesthetic decision. Now, I highly doubt they could turn in a compelling drama even if they wanted to, but they play to their strengths by not even trying.
Sharknado and
Mega Python vs. Gatoroid have many a hilarious moment.
Anyway, people who think Hollywood is worse now are clearly forgetting the endless stream of bad movies that it has been shovelling forth ever since it existed. Look past the acknowledged classics of any decade from the 1910s through to the 2000s and you'll find (in addition to some hidden gems, obviously) hundreds of god awful, mediocre, insipid, uninspired titles. Because Hollywood is a film
industry it produces large numbers of movies every year, most of them are going to be mediocre or based on dumb ideas like
Space Invaders as a matter of course, it's always been that way.