Isolated changes aren't a myth. FAANG and others leverage the isolation brought by service separation every day. For very large services, a monolith makes it difficult to test services independently.

I personally don't like the word "microservices" since it implies that services have to be micro. For the last few years I have worked on service oriented systems where the individual components are sometimes pretty big - one could say almost monolithic :).

Splitting a monolith into separate services exacts an operational price. Engineers should be honest in assessing whether it's worth it. Sometimes it is, sometimes it isn't.