As a hard-core game show fan, I would naturally say, "Of course they would succeed in the daytime!" But, that's not what you're looking for, I assume!
One thing I should say first: At my school, I usually eat dinner around the time WOF, FF, and Pyramid come on. We do have a place in the cafeteria with a big-screen projection TV, so I usually put it on whatever game show is on at the moment, and, whenever I look around, I notice something peculiar: Whenever any other show is on TV, other people around the TV don't really look; they just do homework. When a game show is on, EVERYBODY looks and most people will stay and watch until the end, even if they're all ready to go. I find this amazing, especially since this has happened EVERY TIME I've put on a game show.
From the above, I've concluded that, as much as people hate to admit it, they love game shows. What's more, they love game shows that challenge their brain; this reaction above doesn't happen with any of the relationship game shows. So, if the networks went back to shows like they had in the '80s, I think it would be a modest success. It won't be groundbreaking success, but I think it would probably match the numbers that the talk shows get, and maybe do a little better.
Everybody whom I've talked to says that talk shows, especially the trashy ones, are getting old, and they're looking for a change. Why not daytime game shows?
Anthony
P.S. I had a friend over today, and, even though she doesn't watch game shows, she STILL sat down and watched until the end of "Nick Arcade!" And, no, I didn't make her do that!