I always wonder if it's a generational thing where an old guard of veteran TV/Film crews who came on the scene in the 70s reached their peak in the 90s and have since died off without passing on knowledge because the tech changed.

i don't know, i feel like it's a fairly recent thing and came about with netflix - HBO shows looked pretty fantastic in the early to mid 2010's Better Call Saul is a recent example of a show that looks fantastic feels like a deliberate choice (to save money??)