I think we can all agree that it’s a bad translation. But unless you can come up with a easier way of saying Mazel Tov in English, I’ll stick with good luck
I was unclear above. The reason that there is no mazel because we can ask Hashem to override the mazel through tefIla and because of maasim tovim. See the end of Maseches Shabbos.
Yitzchokm, “mazeltov” in English is not “good luck”, it’s “congratulations”, or just “mazeltov”.
But the OP is wrong. It is normal Jewish practice to wish people “mazel in brocho”, or “es zol zayn mit mazel”, etc., and nobody of any significance has ever had a problem with it.