Those aren't coming from Reddit - Reddit links are rel="nofollow" and have been for years. What's happening is that scraper sites and automated blog networks are picking up your domain from wherever you've had it visible (could be a SaaS directory, a guest post bio, or even a mention in a forum thread). They then auto-list it across their garbage PBNs.
Google's link graph largely ignores these now - they're classified as "unnatural" or low-quality signals and are weighted at near zero. No disavow file needed, no action required. The only thing you might want to double-check is whether someone's using your brand name in anchor text on actual spam sites, even then, Google typically discounts it.
If you're seeing a spike in referral traffic from these domains, that's a different story - but if it's just backlink reports in Ahrefs or SEMrush, ignore them. I've had this happen with every project I've launched. It's noise, not a signal.
