Have you considered using a provider that might help eliminate some of the operational burden of running your apps?
At a very high level, when using the big 3 and hosting that's raw infra you're going to find ways to pay for _keeping things running smoothly_. At least the big three have happy paths to avoid some of the operational burden (hidden among many many foot guns).
Full disclosure I work at noop.dev [1], a hosting provider trying to shift the focus of developers from infra-level abstractions to application-level abstractions.
I'm probably biased, but my instinct is that concerns over lock-in are totally valid, but the cost of avoiding is higher than the penalty of embracing.