As I said elsewhere, this isn't a surprise and nor is this related to Trump. Television is dying in general, late night and talk shows being hit fairly hard during all of it. The studios put so much money into these shows but they're constantly losing money because people are watching more on YouTube than anywhere else and they can't get the same money there.
Don't believe me? Believe Jimmy Kimmel who said a couple of years ago that he has no hope for Late Night as a format to be able to continue in the future. Kimmel will probably be the next to go. Large amount of money goes into that show and Kimmel doesn't have all the shows Fallon has which means he won't have the same pull in protecting himself.
People are gonna keep shouting this is about Trump and the merger but these conversations about Late Night and whether it's worth it have been going on since Craig Ferguson left. Then you've got the fact that Conan, Samantha Bee, and Corden all had their late shows cancelled and no other late shows replaced them. If the studios didn't replace them with another talk show it's because they couldn't see the money in filling that timeslot with a talk show anymore. Not to mention the fact that Colbert had about 3.4 million viewers in 2019 and was #1 Viewed Late Night Host. He currently has 2.5 million viewers and is #1 Viewed Late Night Host. Where do you guys think that those people went, exactly? Because no other Late Night show got a big bump of 900k viewers. Or where do you think Conans viewers went? Again, no big bump to Kimmel or Fallon. People just aren't watching Late Night anymore.
This isn't a conspiracy. It's a trend. A blatantly obvious one that Late Night hosts have been joking about for years.
Edit: Keep the downvotes coming. If it helps your desperate little fragile brain sleep better at night, then by all means. You pressing a down arrow isn't gonna make me sleep any less but if helps you sleep like itty baby? Go for it.