Of course a high school wrestler will beat most other kids at school - his athletic training significantly overlaps what is useful in fighting, whereas none of the other sports do. IOW, you’ve got a trained conditioned guy going up against an untrained guy. Pretty simple. A kid with 3 years of boxing would also beat most untrained classmates too.
Pissing matches or drunken fights are seldom if ever fought between two equally trained and motivated fighters with both being ready to go; there’s almost always lop-sidedness going in which can distort how good someone really is… was he and his style great or was the other guy just an over-confident drunk who chose the wrong moment to look to the side at the waitress?
Once you start comparing wrestling to other trained people in different things, it still comes out pretty good - though the wrestlers will usually need to throw in a few things to finish a fight that they may or may not have been shown along the way; ground & pounding with headbutts isn’t in the normal high school curriculum.
If you know what you’re doing, being on your back with someone on top isn’t very dangerous against most guys if it’s just 1 on 1 in a controled environment… then again going to the ground on top or bottom are both equally risky in a real-life scenario… but from a technical point of view I’ve fast-forwarded through hours of boring no-action footage of even mediocre fighters getting put on their back, tying the head and hands of the guy on top up, and just laying there. You can’t do much to a guy who just wants to tie you up from the bottom. Untrained guys on their backs?, well yeah - it can be over pretty fast.
Again if you know your stuff there are several things you can finish the guy on top with. Here are a few pictures from fights where just that happened:
Triangle choke (coming up in a few seconds)
Another Triangle (sunk in this time)
Armbar
Note that the first two pics are of mulitple title-holding wrestlers getting caught; one of them an olympian. Finding good action pics is hard, but there are lots of things you can do from your back. It’s not a place you ever want to go, but it’s far from hopeless.
Giving your back to a submissions guy is pretty risky, unless you are going to escape and/or get back up real fast. Here are some pics of what can happen when you “turtle up”:
Rear naked choke
Knees to the head
Punches to the side of the head (yeah they hurt)
Notice it’s the same guy getting kneed and punched in two different fights; he lost twice from knees to the head while turtled - and he too is a former olympic-level wrestler.
I don’t mean to pick on wrestlers here, and checking MMA records of fighters who started as wrestlers shows they usually do a bit better than most others; however they are not heads and shoulders above any other style. The OP was asking about wrestlers, and there have been some questionable things written here about their capabilities (and those of punchers), so here are some more pics from NHB events of wrestlers going against strikers and loosing:
Not a KO loss but the wrestler couldn’t get this kickboxer down or keep him there even though he had over 20 minutes. Looks like he didn’t like those fists and feet coming at him.
The same wrestler in overtime again after his opponent keep getting away. This was a KO, and a particularly hard one at that.
Sorry Mark, but you take a good picture :D. (This guy actually did very well in NHB, but he definately had his weaknesses and off nights)
Another big wrestler having a tough time dealing with punches.
Just over a month ago Wrestler about to be KOd by a striker’s nasty knees.
One-punch KO
This last one isn’t of a wrestler losing, just a shot of what a good punch can do. This fight lasted 30 seconds total, about 2 seconds of that was the set up and punch that finished it.
Now those pictures don’t really prove anything on a large scale, and I don’t mean them to. I just provide them so that I have more than words for people to assess my opinion on. They are almost all of very popular fighters at the tops of their games, and you can check their records and find more info on them too. Just to finish, almost anyone who has trained in one of the many practical fighting arts will kick the ass of an untrained guy. If you only happen to see a wrester doing it in your lifetime, then that style will appear pretty good. If you live in China and the local college tough guys are Kung-Fu men, then that style will appear pretty good too. Trained people in most anything shouldn’t be messed with; one style will kick your ass in 20 seconds, another in 10 seconds. You’ll still loose against either one of you don’t know what you’re doing.