Maybe Lauda wanted to hide his gender right from the beginning, but somehow I think that he had just a bit of fun with people guessing it because of his name ends with an "a" or whatever else started all that, even though when I heard his name for the first time it didn't sound as a female name since it reminded me of a famous Austrian F1 driver Niki Lauda.

Perhaps you should verify with other Croation/Serbian well known posters such as Marlboroza to verify the grammar used by the persona "Lauda" was indeed male in vocabulary.