No Stupid Questions

Tracking of reads = when you read someone's post, there is a permanent log record made, e.g. in a db row associated with the user, that @aski3252 read that post. That is somewhat different from normal httpd access logs that associate only with IP addresses and which typically get distilled down to aggregate data, and prefeferably discarded after a short period. Where I worked, we kept logs around for 30 days for stuff like abuse investigations but deleted them after that. In fact with a little careful design of the log data, or if the query is sent by HTTP POST instead of GET, the parameters that identify what you were reading will usually not be logged at all.

It's not mostly an issue of selling data for marketing purposes. It could also be extracted by cyber attackers, seized by law enforcement, or whatever. The only way to stop that from happening is to not retain the data in the first place. "Marketing purposes" is a smoke screen anyway. E.g. if you are a regular lurker on a community about workplace organizing, that info will be more valuable to your boss than it will be to some advertiser or marketer. So the real customers of internet usage data (and phone records etc.) are far less benign than "marketing" organizations.

It is not necessary to record voting data except to prevent you from voting twice on a particular topic. So if voting closes (say on a poll), all the data about who voted in it can be deleted. There is also no need to remember HOW anyone voted. It's enough to remember that you voted on a particular topic, and increment the relevant vote counter. That is also how real-world elections work. See also the topic of "receipt-free voting" in cryptography.

I agree with you that if you actually publish something on the site, there is a certain amount of disclosure unavoidably associated with that.

Facebook was notoriously evil and I actuallly have all their domains that I know of blocked from my computer at the DNS level in order to avoid their spying. That Reddit tracks posts viewed is new to me but I guess not that surprising. Usenet never tracked posts viewed and basically couldn't. Wikipedia emphatically doesn't track that, though it doesn't track view counts. Arxiv.org doesn't track (or at least publish) view counts for individual papers (see here) though they do publish stats about the entire site. A real privacy focused site would avoid publishing any about what viewers are doing. There is a whole topic in cryptography called private information retrieval about how to run a server in which the clients can verify that the server can't know what they are reading. This is what Lemmy should aspire to, imho. (Aspirations aren't meant to be achieved literally, but only to provide guidance).

I may open a thread in /c/privacy@lemmy.ml asking about this, but the answer might be to launch my own Lemmy instance and retrieve all of the Lemmy posts so I can browse the ones that interest me without leaking any info. I'm sort of in a position to do that, but most people unfortunately aren't.