This is usually not because the artists involved are bad at what they do, but one or both of: deliberately catering to "bad" taste that is nonetheless popular, or making work worse than it could be to make the cost/demand curve line up better by saving some money on aspects that won't make more money if they're better (see: the MCU, which I actually like but which definitely avoids risks that might improve their films, and cuts corners in ways that don't matter much for the bottom line); or, organizational/managerial failure on projects that require large organizations to attempt in the first place (film is especially prone to this).
But one thought this thread is provoking is related to this well-intentioned but self-destructive (imho) 20th century cultural narrative that talent as a prerequisite for art creates a tyranny where certain people are allowed to express themselves with dignity while the vast majority are not.
Sometimes I like this narrative, sometimes I hate it. But regardless it undeniably had the effect of leveling the playing field while retaining the same old gilded-age toxic celebrity hierarchy, which simply seems to have had the effect of letting the wealthy and powerful silently dominate cultural / artistic production, which this thread already started to touch on a bit.
Ie, the now fairly ubiquitous experience of walking into an art museum, seeing a blank canvas propped on the floor next to a neon light. Thinking "Anyone could make that so whys this person rich and famous for it?" Shrugging, leaving and not going back to an art museum for another decade.
I enjoy that kind of art in the right context but it clearly has a destructive effect on peoples natural ability to care about art and have a healthy creative practice themselves.
And yet, mediocre content abounds in the media. How should that be explained?