I have been looking at using both of those. I have used TCL before but it was a while back, but Lazarus does have a visual designer which I have played with a bit.
I am not sure which makes producing cross platform binaries easier. I ran into a few issues the last time I tried TclKit I ran into problems so Starkits may not be an easy solution anymore.
Lazarus is excellent. It is very user friendly once you get the hang of it, and you can use Delphi books to learn the language. It also produces static binaries that make it easy to distribute your software.
Yes, both Tcl/Tk and Python/Tk are great in 2025 for doing simple GUI programming and this fact does make me sad. Or perhaps we've found the global minimum? Who knows.
Infuriatingly, Tcl/Tk (and other things which use Tk) is still light years easier for doing basic GUI programming than anything that exists in 2025.
How the hell can decades have elapsed and Tcl/Tk, Hypercard and VB6 are still vastly better for GUI development than anything we currently have?