especially since most other people would probably be less effort to track down.

ding ding ding

I have politically active friends who are supposedly privacy minded blasting their takes on facebook and complaining when they get banned for inciting violence. Most people are terrible at this and the algos the feds use probably aren't that great. I'm more likely to get grabbed randomly.

Also, other sites on the Net can collate links posted to reddit and the users and times that they were posted with users accessing pages on their own site. For example, if you've posted a sufficient number of youtube links, youtube can possibly link your reddit account and youtube account, say, as belonging to the same person. Just about any popular site can link your reddit account with your IP address. And your facebook account with your IP address. Etc. And thereby link reddit accounts with facebook accounts in cases with long-lived IP addresses. If X is a scrapable site on which users with fixed pseudonyms can submit links and Y is a site popular enough and has enough content, then Y can collate user accounts on X with IP addresses. This is not to say anyone is doing this. There are not many sites that meet the criteria to be a Y. I would say it includes mainstream news sites. The authorities could compromise some of the Ys or create their own through astroturf and thereby link users on the Xs with IP addresses and then with location.

These days, this might be a bit harder because reddit closed up when the AI companies started scraping. I don't know the situation with Facebook with regard to scraping. If it's scrapable, they've got your name linked to your reddit account.

What I've said about reddit equally applies to lemmy, even more so because lemmy is open by principle.