I dont disagree, but you can horizontally scale a monolith too, no? So scaling vert vs horiz is independent of microservices, its just that separating services allows you to be precise with your scaling. Ie you can scale up a compute heavy micorservice by 100x, the upload service by 10x but keep the user service at low scale. I agree that one can vert scale, why not. And I also agree that there are probably big microservices. At my last workplace, we also had people very bullish on microservices but for bad reasons and it didn't make sense, ie ideology.