I agree, mostly. What do you do for people without an ID (and without a parent)? Think of the number of people at a Taylor Swift concert who are under 18 -- a lot. Also, checking the name between ticket and ID will slow down entrance by 2-5 times, I guess.
I was recently at a Festival that requires ticket + ID (https://www.resurrectionfest.es). The key to success was to put a little more personal at the gates, maybe 15 people instead of 10. But it is also true that we have the ID document issued in our early teens it not before. Each ticket verification takes 3 more seconds extra to verify the ID matches, no big deal.
Said festival does their own ticket re-sale to avoid scalping but mainly to avoid shady sites that are known to allow the selling of counterfeits. You can only cede your ticket, not sell it. It is not perfect (e.g. if you don't find a buyer for the same price, you can't sell it at a lost to recoup some money. You get your ticket back) but at least is not as bad as the one from Ticketmaster.
