This company builds a team vacation tracker. As long as it's reliable, their customers could not give a rat's ass whether it runs in AWS, Google, or Joebob's House Of Ill Compute. Every engineer hour spent creating abstraction layers and docker containers and whiz-bang multiplatform plumbing is an hour that could have been spent working on something your users actually care about.
Switching clouds is a cost optimization. You have to be an enormous company (or in a resource-intensive domain) before this is more productive than building features. It means you've moved out of the growth phase and into the "how do I milk what I've got" phase.
Vendor lock-in is something that engineers care about because they like playing with tech. It's cool switching platforms or databases or whatnot because it really feels like hard, sophisticated work! But it doesn't move the needle.