tinyE: Not with me.
I don't block anyone.
ANYONE can PM me. I may not reply, but you WILL NOT BE BLOCKED.
Oh, I didn't mean I block people. I meant that if someone doesn't pass the above test, I just leave them there for a day/week/few weeks if I haven't already due to being busy, and then eventually click "Decline Request" if I haven't been able to figure out why they added me, and they haven't engaged in any communication with me at all, especially if they haven't communicated visibly with anyone at all publicly previously.
The chances of someone being worth accepting a friend request just about anywhere in social media (non-professionally) who:
1) Added you without any communication.
2) You don't know them or are unable to determine who they are or why they added you.
3) They have no public communication record.
4) You haven't initiated any communications publicly that would/should prompt anyone to add you (a giveaway or social interaction request etc.)
5) Google shows no results or bad results for the nickname.
... is pretty much a non-starter. In almost every case I've ever seen on Facebook, gaming sites, other social media - it is a spammer or some kind of scammer. In a very very small number of cases it is someone who is trying to be friendly by reaching out without communicating in the process due to having social skill deficiencies of some kind. In most cases, it is easy to tell them all apart though and make a reasonable choice.
I generally only block people on any kind of social media, if I have found that they are absolutely demonstrably a scammer, spammer, or I perceive them to be extremely toxic and I've had or am likely to have an unwanted interaction with them. The rest aren't worth the time to take that extra step. :oP