> Cloud makes sense when elasticity matters; bare metal wins when baseload dominates.

This really is the crux of the matter in my opinion, at least for applications (databases and so on is in my opinion more nuanced). I've only worked at one place where using cloud functions made sense (keeping it somewhat vague here): data ingestion from stations that could be EXTREMELY bursty. Usually we got data from the stations at roughly midnight every day, nothing a regular server couldn't handle, but occasionally a station would come back online after weeks or new stations got connected etc which produced incredible load for a very short amount of time when we fetched, parsed and handled each packet. Instead of queuing things for ages we could instead just horizontally scale it out to handle the pressure.