At least from this blog post, I wouldn't take his advice on MRR. He's optimizing in the wrong places; he'd be better off spending $100 per month on hosting and focusing on MRR than focusing on bringing hosting costs down to 0.2% of revenue. There's a middle ground without K8S where you use your cloud's autoscaling app hosting and a small, replicated DB. He strawmaned the enterprise approach, and he's trading off a lot of toil for uptime.