this years set up is as close to exclusive windows for the S16 as you can get and all eyes on one game is what advertisers want these days so be prepared for this to stick unless the Monday/Tuesday ratings crater

What do you mean when you say exclusive windows? I promise you won't see anything like this again under the current media contract and that doesn't expire until 2028. The Monday and Tuesday games work much better for TNT and TBS, but they aren't as good for CBS.
CBS had essentially the same rating for the games last Monday than they did with the primetime lineup the Monday before which was about 6 Million viewers. They were second in ratings last Monday but they didn't have the bachelor or, they finished behind the voice and that number would have finished in third the week before, just like their regular line up.
However, the 4 million they got on the first night of the tournament won the ratings by far, because again Friday night is a network television dead zone. I really don't think that CBS is willing just going to give away two weeks, in the March book, of kicking the crap out of the other networks for just another week of MacGyver and Magnum P.I.
playing the S16 on Saturday & Sunday means every cbb fan is watching 1 game instead of switching between 2 on Thursday or Friday night. This is similar to how the 2:30 time slot on cfb saturdays and 3 pm nfl sundays have moved to fewer games in the last few years.
The networks don't care about that, they only care about ratings and ad revenue. The ratings are and always have been terrible on those afternoon weekend games, especially the Saturday slot.
Anyway, that's neither here or there because the schedule isn't changing before 2028 anyway because of the complex media deal involving split rights. The NCAA also has sites and dates booked for the preliminary rounds through 2024.
Now when the tournament eventually makes it to 96 teams, then we'll see a different schedule. First week will probably go Thursday-Tuesday, second weekend Friday-Monday, final four unchanged.