SKS' and other surplus firearms are popular among a younger crowd because they're cheap, easy to feed, and recommended highly on the internet. Younger people may generally be more hotheaded.
Or it could be just coincidence
M1 carbines are no longer cheap to buy or feed, and they tend to be purchased by the older crowd who are no less hotheaded.
You want to see a bunch of M1 carbine collectors get in a lather, post a question about which is better to refinish a stock; boiled lindseed oil or raw lindseed oil. It's downright amusing to watch.