I know it blocks a use of your information against you (targeted ads). And any external source is a potential leak (e.g. the kinds of things that CORS is supposed to reduce).
But does an ad blocker specifically leak more, or just reduce the incentive to collect that information?
This blocks most existing tracking methods. The only thing you're not protected from is first-party tracking by the site you're actually visiting, which is impossible to fully protect against.
Incidentally, just blocking JavaScript with NoScript kills quite a lot of ads (obviously, not first-party ones if you've white-listed their JavaScript for site functionality; but I try to avoid that when there isn't real demonstrated value) without any need for an explicit ad blocker.
If that is an acceptable compromise, you could also try ditching the Internet altogether, as that not only blocks all online tracking, it also blocks a lot of fraud, misinformation and all kinds of harmful content.
You literally (actually literally) can.
Sure, images may no be present without JS lazy-loading them. Accidentaly, NoScript also fixes a lot of websites. Publishers are often paywalling posts via JS and initial HTML is served with full articles.
You're trying to imply that ublock lite doesn't do that. It does, including javascript files. The full uBlock does more things to prevent tracking that lite cannot do. But "intercept requests at the network level" isn't one of those things.
It looks very stretched, but the real magic happens when this data is sold in bulk. It allows recouping who is where. Your target person may or may not be in each dataset, their location isn’t known like clockwork, but that allows determining where they work, where they sleep and who they’re with. One ad is useless as a datapoint, but recouping shows reliable patterns. And remember most people on iPhone still don’t have an adblocker.