This only goes so far, though, with frameworks. In my experience, the vast majority of people that make claims about a particular framework do not understand the abstractions they are building upon. In fact it is sufficiently reliable that I have found this to be an excellent hiring signal, to probe how well a person understands the abstractions in frameworks they use, but also to probe how they diagnose and fix holes in their own knowledge.
Using frameworks, you are still using the language itself to command the frameworks. For example, if someone claims oneself as a React programmer, nobody would assume that someone didn't know Javascript.
So to efficiently use one framework, you should master both the language + framework. In other words, the complexity not only remains, but also accumulates.
But this is contradictory to low/no code's selling point, as they are targeting non-programmers.