I noticed that the first thread I reported as spam, instead of being deleted, has been moved to the alts section
On which grounds you reported the thread? As you know, scam is not moderated and its very hard to prove that project actually paid someone to shill in their topic so its no surprise that thread wasn't deleted.
but the comments from the alts are spammy as hell. Take for example this one in the second thread
My suggestion is to report those spammy posts instead reporting thread where spamfest is happening.