Yeah like what if judges be like hey I recognize this and give it more points
Judges being familiar with pieces might backfire on you--they might think that your arrangement of the piece ruined it. (Sadly, I'm like that with several VGM remixes I've heard.)
It's easy to get a cool, sort of mystic feeling when I'm listening to vgm I don't know very well. It gives me a chance to check out a new soundtrack and appreciate different franchises. And then I'll be in awe of your mastery of music I wasn't even familiar with.
That reminds me of my time listening to
Live at Grillby's, not recognizing half the UnderTale songs, and being convinced by insaneintherainmusic's performances of them that I was listening to generic jazz.
Sadly, it's a catch-22 for me: if I'm not familiar with the song, it's unlikely I'll remember it (I typically remember 1-3 songs from each video game I play, and this includes video games with few songs in them), and if I'm familiar with the song, there's a fair chance I'm tearing apart your arrangement's melodic, harmonic, and rhythmic accuracy. (The amusing part is that I've listened to a few VGM songs where NONE of the arrangements I could find get it 100% melodically or harmonically correct.)