A vort is a new simcha in the following sence. Until 30 years ago, people made a Tenoyim with a seudah, which is something discussed numerous times in the seforim and halacha.
For some reason we dropped the idea of writing Tenoyim (in American Litvishe circles), and had to rename the party as a “vort”.
Have a tenoyim is still the norm among Chassidim, as well as by Litveshe in Eretz Yisroel.