Re: "there are much more suitable options for that"
> Feel free to name them... Eclipse? Lazarus?
Not entirely sure what "GUI development" is. My experience with developing graphical user interfaces, or GUI-based applications is mostly limited to Qt, and I used to use the Qt development tools for that.
Other than that, my main workhorse is Kate, backed by the power of Git, GitLab, and various continuous integration and deployment tools, so most stuff happens automatically when it has to. If you are pointing and clicking while doing development, you are probably doing it wrong, and certainly doing it slow.
Apologies if I got the wrong end of the stick though. Just not entirely clear what the question is about.