It's not even that. Most demographics are really easy to market to and create content for. Especially in this day and age of data being so easily obtainable.
The problem is the insatiable nature of media companies and the overall general concept of infinite/unsustainable growth and the expectations it creates. You have companies that are trying to appeal to demographics that weren't part of the existing demo or are trying to create such broad, mass appeal that you either end up alienating your existing market (do I really need to go into particulars here?) or are such a bland, homogenized mess that we end up with crap like 2023 Night Court.
Instead of creating media that might have crossover appeal but will almost assuredly have appeal to a niche demo within your market, you end up with garbage like Velma or She-Hulk.
Like, we had a 'soap opera for men' and it was wildly successful. Blew the fucking doors off of the television medium. It was called the Sopranos. It didn't try to create a 'mafia show, but for minorities/women', and, in fact, there was a 'soap opera for women' that was right there on HBO and even included diversity by having the first horse as a lead since Mr. Ed with Sex in the City.