This is not true at all. Electricity prices are crazy and hardware is a lot more expensive for us (not affiliated with DO, I run a PaaS service) than it was 2 years ago.
I don't think Intel and AMD based servers are getting much faster or cheaper anymore for custom workloads (web apps, etc)
Employees, electricity, physical space, infrastructure, etc.
Computers were already pretty cheap, and engineers are not.
I would imagine metal and silicon are a small portion of DO's operating costs.
its all of us trying to maximize TC that drives up the cost!