It would be possible, though if you participated a lot, you'd leave a lot of writing to be analysed. That would at least deter the casuals.
In my case, I post using my first name and most regulars would know who I am. It's a sports forum and people have recognised me at games, etc. I've had people look up my phone number and call me aggressively about things. I've had countless legal letters and threats. Someone doxxed my parents in the early days. You quickly learn how many unhinged members of society we have.
