He may have overestimated the number, but his point still stands. Football players take a lot more hits than hockey players. Some of them (interior linemen, linebackers, fullbacks) take fairly forceful hits, frequently to the head, on just about every single play (and probably multiple hits on a lot of plays). And even if you don't practice in full pads at all during the week (pretty sure they do at least one day) then that's going to be on the order of 100 or more hits every single week.
Hockey players take only a handful of hits per game, and those are, by and large, body to body. Nobody leads with their head, and when people actually take shoulders or elbows to the head, there is usually a pretty heavy penalty levied against the offender. Of course, hockey players don't wear very protective helmets so when they do get hit, their protection is compromised.
Not that it means much, but I played rec hockey (roller and ice) for about 10 years and I don't think I took one shot to the head in that entire time. Of course, rec hockey frowns upon hitting, which is why I said it doesn't mean much, but hey. ;)
It's not just the shots to the head that just do damage, it's impact to the body of any kind that causes the brain to crash into the skull. You could get a concussion from a hard kick or punch to your body, which is why I said in earlier posts why it's so important to build the neck muscles that support the skull and reduce the bobblehead effect.
Not trying to nitpick but football teams average 66 offensive plays per game of which most players except offensive lineman swap out for different packages, and not every play results in a significant impact. Conversely, average number of hits in a NHL game is 45 (20-25) per side, but the NHL season is over 4 times as long.