PaaS takes away your flexibility: […] sometimes, you also want to use the compute to run cron jobs, run background jobs, or host a small service. With PaaS, you don’t have the flexibility to do so. […]

I don’t really agree with that. I’m using AWS for that, and for my “small cron jobs” I simply create a lambda for them. Then you can create a CRON rule in Event Bridge and schedule the lambda to start whenever you need