Looks matter a lot when it comes to even making friends with women. The fact of the matter is most women do not even want to be around ugly guys and often times they will actively push ugly men out of a social circle that they're in.
Even when it comes to making friends with guys, looks matter to an extent.
In general, being good looking makes people more likely to trust you, makes people feel more comfortable around you, and generally makes people more likely to assume positive things about you and helps a lot with first impressions. Likewise, being ugly makes people more likely to be wary of you, and in some cases even afraid of you (if you're the low trust kind of ugly). People will be far more likely to assume negative things about you. This includes everything from people thinking "that guy's a loser" to "that guy is a potential rapist".
With that said, it's obviously possible for an ugly guy to have friends and even have a decent sized social circle. I was a 1.5/10 before surgery (uglier than blackops2cel) and even I had friends and was socially active in my late teens and early 20s. Granted almost all of my friends were male and a disproportionately high percent were ugly incels or autists.
But if you're young (22 or under) and have no friends, you have other things working against you besides your looks.