wxWidgets 3.2 now supports wxDate In OSX/Cocoa native version, this style is supported on macOS 10.15.4 and later, and invoked by left-clicking on the date control
https://docs.wxwidgets.org/3.2/classwx_date_picker_ctrl.html

Suggest we now remove the workaround and simplify code that was implemented and invoked by right-clicking on the date control
#3139