The problem for many parents is that all the other kids have it. It's not always easy to develop a relationship with your kid to convince them that they don't need to conform and have friends.
So I can imagine that many parent would be relieved if access to social media was slightly more complicated, such that maybe it would be more normal to not have access to social media.
I have a simple example: when all the kids have a smartphone, it is very hard to tell your kid that they cannot have one. When all the kids have a shared culture built around social media, it is very hard to tell yours to not conform. "It's okay my son, you don't need friends. Anyway the parents of all those kids are bad parents".
I don't have children, but it doesn't sound completely weird that parents may say "we should prevent most kids from accessing social media, so that my kid wouldn't be the weirdo if I don't let them have access".