I guess people paint with a broad brush based on their experience. nginx is a pretty fantastic piece of software - it runs a significant proportion of the web. nginx retries put / post requests if the application server times out. This quirk can be dangerous if you don't know about it, and nginx really should allow you to configure it, but it can be patched, and only affects you if you have multiple application servers.
I guess people paint with a broad brush based on their experience. nginx is a pretty fantastic piece of software - it runs a significant proportion of the web. nginx retries put / post requests if the application server times out. This quirk can be dangerous if you don't know about it, and nginx really should allow you to configure it, but it can be patched, and only affects you if you have multiple application servers.