Managed services are always more expensive than DIY FWIW. You're paying to make running the product someone else's problem.
DIY only make sense at a very small scale or very large scale, everything in between is usually best offloaded to those which do it as their core competency.
It seems like very small scale has the highest leverage of utility-priced services (and often fits into free tiers of many).
More broadly I’ve never used managed service that would “just work” and wouldn’t require substantial configuration and often times bunch of workarounds but maybe those exist
Yes, in theory, in the middle scale, you should outsource things, but in practice, it only works if the managed service is at the right price.