In Defense of KDE (Score 2)

1.) It was founded by Matthias Ettrich who developed the very fine program Lyx, but then used the non-free toolkit xforms for its GUI, instead of e.g. using a free alternative like TCL/TK.

Tcl is a scripting language. Tk is a widget toolkit originally devloped on top of Tcl. When Lyx was being developed, I believe there were no Tk bindings for any other languages. Developing a full featured WIYSIAWYG editor with a scripting language in the days of the 486 in not something I would want to try. In the days when Lyx was developed, most Xwindows software was based on either the Athena (Xaw) toolkit that comes with Xwindows, or Motif. Athena is not particularly pretty, and lacked anything beyond the basic widgets. Motif is even less free than xforms. I believe there were some open source toolkits available, but I don't think any of them were particularly mature at that time.

When I wrote my first linux app, back in early '96, I also used the xforms library. It had a nice dialog editor, looked nice, and was easy to develop with. Back then there were still many areas in which usuable open source applications were unavailable, and people weren't quite as religious about using only open source. (Or maybe it only seemed that way to me.)

Irregardless, I hope the fact that I also used a non-open source toolkit in the past does not invalidate any open source software I write in the future.