At a previous job I was able to cut our infrastructure expenses by a lot (70%) by essentially have our infra being 1 load-balancer, 2 beefy application servers and 1 (+1 failover) PostgreSQL database. Each of the application server costs 300~ Euros p/m , 24 cores and 256GB of RAM. I have not experienced the same cost to perf ratio anywhere else.
Disclaimer: 18 years in different ops roles
I also have ~10 smaller hobby projects (<100 monthly active users) which could easily fit inside the smallest cloud services, but the smallest on offer seems to be $5/mo, so $50/mo in total. For $25/mo I can get a pair of bare metal servers which host all of them with failover and a ton of capacity to spare.
Then my actual day-job is at the opposite end of the scale, where we build our own datacenters...
I am very confused by the movement towards using the cloud for everything, because I work at all sorts of scales, and can't find a cloud host who works well for any of my use-cases :S
Just a couple off the top of my head:
1 - Incredibly large infrequently run / ad-hoc workloads
2 - Companies with such a horrendous internal work environment that they can't retain decent technical talent, where managed services can substitute to some degree.
Sure there are challenges, but when there are issues, we can figure it out. We don't have to wait for support.