What to do if you are turning 30 and earning 43LPA CTC, and your friend casually assumed it must be obviously base?

Nothing, you keep doing your job as long as you're happy with it.

Your friends opinions and misconceptions are his problem, not yours.

Some people earn a crore at 30 in MAANGs, some hardly 10L in WITCH companies. You are doing better than many and can still do better is all