Agreed, it’s why I said “at any kind of scale”.

There’s a sort of arguable sweet spot where someone motivated and knowledgeable can manage their own hardware, even if it’s just rented from Hetzner etc. But that just doesn’t scale.

Once you do try to scale that - not just the hardware but the staffing that’s needed to avoid a bus factor of 1, to ensure the required uptime especially if it needs to be 24x7, to handle disaster recovery, failover, security and compliance issues etc. etc., you quickly run into all the reasons that infrastructure management services and other computing services - i.e., cloud - have won out so definitively.

If you’re small enough that none of those things matter very much to you, and knowledgeable enough to run your whole system yourself, and have the time and inclination to deal with it, go for it! But such people are outliers who are really indulging a hobby more than anything else. It generally makes extremely little business sense.