Comment by twodave
I came here to say the same. If you’re arguing either for or against microservices you’re probably not thinking about the problem correctly. Running one big service may make sense if your resource needs are pretty uniform. Even if they’re not you need to weight the cost of adding complexity vs the cost of scaling some things prematurely or unnecessarily. Often this is an acceptable precursor to splitting up a process.
You can still horizontally scale a monolith and distribute requests equally or route certain requests to certain instances; the only downside is that those instances would technically waste a few hundred MBs of RAM holding code for endpoints they will never serve; however RAM is cheap compared to the labor cost of a microservices environment.