Sounds awful though tbh 10th board is just a joke getting 100% in most subjects is quite trivial. The thing I hate about language subjects is that no matter what you write teachers always deduct marks Which is the only reason that your percentage goes down. In my case, it was worse in Hindi since I could never (since 1st grade to 10th) understand the difference between small and large vowels sounds and when to use them and teachers deducted 1/2 marks for every spelling mistake.
I heard Sanskrit papers are mostly fill in the blank/objective type papers. Maybe that's why its possible to score 100%.