By EU law they are only allowed to track you if you click agree. If you don't click anything or disagree the shouldn't do it (They need active consent). However the american tech giants are known for casually breaking laws since they can afford the fines.
You didn't delete anything. You told reddit to delete stuff, but whether they actually did that is a different question. It isn't public on their website anymore, but the data might still be lying around on their servers
The important part is that you should have the power to choose who gets access to what info about you. That's what the right to privacy is supposed to enable, and that's what the big internet companies and "anti terrorist" legislation is undermining.
Any other assessment amounts to historical revision.
Your assessment builds on the (unprovable and undisprovable) assumption that an invasion would have otherwise happened. But we can't know what would have happened if different decisions were made. l Wikipedia says that at the time the top brass was split on this decision, and not just for moral reasons.
Also I'd like to mention that whether something is a war crime or not, is, at the end of the day, just a legal question. Back then it wasn't, but by today's treaties killing any civillian under any circumstance is indeed a war crime.
My board lets me set vcore to 2V, what safety lol