There are definitely security concerns. Two things can help, although I don’t think anything can eliminate them:
1) Don’t “collect” friends. Everybody on my personal page is either someone I know, or someone who has been recommended by someone I know.
2) I get friend requests all the time from people I’ve never heard of. Most of them have one or two pics and one or two posts. I delete those without a second thought. If they seem more legit then I try to figure out how they might know me or someone I know, and then I contact the people who I think might have sent them to me. No verification of who they are means I delete them too.
My current Facebook page is only to keep in touch with family, and consist only of family members. That is why I am reluctant to get Bianca popping up on my other FB account following your experiences. I can see my family scrutinising a picture of Bianca. ‘Looks familiar but who is she??’🤣🥴😮