Ask HN: How do PaaS hosting providers enforce user policy compliance?

I am curious about the engineering and operational side of running a PaaS hosting provider like Render. How do these platforms actively monitor and enforce their Terms of Service efficiently without hurting legitimate application performance? Specifically, I am interested in how they handle this.

Recently, I launched a free subdomain service and got some traction too. But it was banned by Namecheap due to a Google Safe Browsing policy violation, some of my users were registering fishing domains. I can't unban it; I emailed namecheap but have received no reply yet. So, before I launch my next platform, I must learn how I can efficiently do it, specially content policy enforcing.