Current Tcl::pTk and Tkx maintainer here. As I previously wrote: if the program in question is indeed an existing Perl/Tk program, then I agree trying Tcl::pTk(::TkHijack) is a much better choice than rewriting for Tkx. Tcl::Tk or Tcl::pTk might also be preferable for those already familiar with Perl/Tk but not Tkx. But if the program is instead being written from scratch by someone not already familiar with Perl/Tk, then I do think they could be better off following TkDocs.com tutorials for Tkx.
And if someone still prefers using Perl/Tk, e.g. because of its relative ease of installation over Tcl/Tk wrappers like Tkx and Tcl::pTk, then backporting features to Perl/Tk can be investigated/attempted.