If books or other printed material steal from someone else's idea and lazily copy it instead of writing something in their own words, they are likely to get sued for plagiarism. Yet the multitude of refakes (yes, that spelling is intentional) on TV no one seems to care about. While there can be similar concepts, blatantly ripping off an earlier show with the same name and trying to make it modern and sleazy like HBO Max is doing with Head of the Class should not be legal at all. Peter Lenkov doesn't have an original bone in his body, all he is capable of is stealing from other shows just using their name on his crap. His MacGyver refake is terribly insulting to Richard Dean Anderson and the 80s classic. And Alex O is a terrible actor, especially for a series lead. The original Hawaii 5-O is much better, yet the lousy 5-0 refake is what ION decided to plop on their schedule. While I am not happy about the John Mahoney-less Frasier revival in development at a streamer I won't subscribe to, it does have the involvement of the other original cast. And Soleil Moon Frye is involved in the Punky Brewster spin-off. But as for refake crews that had nothing to do with the original, plagiarism rules should apply, at least don't insult the quality of the original by recycling the same title.

plagiarism rules should apply, at least don't insult the quality of the original by recycling the same title.[/COLOR]

Do we know for sure that the modern production has not obtained permission for use from the original rights holders?

There is a lot of exchanging that goes on between pockets. It's entirely possible that a huge entity such as Viacom (or others) might own not only the legacy rights, but might be involved with current production of a "rip off"

I suspect the reason you are seeing more revivals and 're-imaginings' has more to do with the aging viewers of network TV. These shows are 'brand names' that Boomers will recognize, but are updated for the 21st Century. More often they have little in common with the original show.
I guess it's safer than coming up with something original.

They do it because without taking advantage of another show, no one would want to watch these new garbage shows. The name is all they got, then they gotta make it different anyway to be 'edgy.'