From which perspective? If a service is up, but is unable to do anything since another service is down, what good does it do other than increase some metrics on some dashboard. (Note that we are specifically talking about coupled services since the implication is writing to a single db being split up into multiple dbs - a distributed monolith).

Fair point. Unfortunately for me, the only kind of microservice architecture I’ve ever worked with is a distributed monolith - at multiple companies.