@Romulus UNA is big ecosystem, we are making UNA to be scaled, it means that generally it will be slower, but for high load with proper setup it will work better. Old Dolphin isn't scaling good, it means that it looks fast on a single server with several users registered, but to make it scaleable and making it work fast for a lot of users will be difficult.

Latest UNA is already working in some production use cases in a cluster mode.

Also almost any other site (and UNA as well) is usually faster on a single server, when you put all parts apart into different servers, containers, implement load balancers etc, in the result it will be some time overhead, but it will behave better under the higher load than on a single server.

Also we added a lot of advanced features past few years, we'll try to consider to turn off some of the options to make it faster by default (already doing it actually).

Normally you should have server response time around 0.5-1.5 sec, all above isn't normal and need to be addressed. The example is the situation with @gkuhnert site isn't normal, even for big high load site, usually it's much faster.