It all depends on if it is my personal social media account or if it is a marketing or business social media account that I receive friend requests on.
If it is my personal account, I will only accept friend invites from those that I know. For a business or marketing social media account, I am still cautious on who I add but I am not too strict on who I add to those accounts.
I don't really care much about who adds my account on my business social media accounts. The accounts are out there for business purposes and there's no way to rule out anyone from not being a potential customer. This is why I don't decline any friend's request on any of my business accounts.