You exaggerate with the 25 or 30 people. It might take 2 or more debates but all should get equal TV time early on. Later it may make more sense to pare it down. Now you will push away lots of voters as you push away the candidates.
I’m not saying it won’t be challenging. Imagine back when candidates had to literally “stump” in each location by riding a horse and having their audience travel into town.
In the age of technology this should be no big deal.
It isn’t an exaggeration at all, as it is, they are seeking to get it down to 10, from what could be dozens.
Your reasoning about pushing away voters because we eliminate fakes and phonies with no future in politics, like Santorum and Ben Carson, doesn’t make sense.
If it takes two or more debates, the audience tunes out and ends up relying on ads.
Then the guy with the most money for ads wins the nomination.
See: 2012.