Out of interest how do you get the authority to make those decisions and have the existing developers continue working productively after this?
To me it seems like microservices (or cloud, or whatever) is often overused for career/buzzword reasons. The engineers pushing for it aren't asking for your advice, they want to build an engineering playground - denying them the opportunity is unlikely to suddenly make them productive at driving the business forward with a simple stack when their original idea was to play with shiny tech instead.
The only way I see out of this is to have management buy-in to get the microservices and their developers out the door, replaced by more competent people.
> their original idea was to play with shiny tech instead
This is a behavior I would say is very hard to manage out of people and should be screened for aggressively in interviews.
> Out of interest how do you... have the existing developers continue working productively after this?
I don't know if you can in general - by happy coincidence the engineer who had made that plan found his way to the door shortly thereafter