Color me dubious ;-). The change was made because tkinter.__init__, line 1990 has this line
    withdraw = wm_withdraw
There is a similar line for all of the around 30 wm_xyz functions. Prefixing the names of methods of class Wm is an unusual redundancy.  I cannot think of any sane way for tk to know which python synonym was used to call the Python wrapper.

What code using event_generate led you to this conclusion?