Facebook tends towards people you know in real life, so it’d be closer to the echo chamber that is your immediate social circle, but possibly a bit more open because it doesn’t concentrate your attention as much as you probably do offline, i. e. 50 % with spouse and only seeing your high school buddy every two years.

I guess a lot depends on your job: if you work in healthcare or retail, you‘lo have pretty diverse interactions. Software developer in their home office? Not so much.