YC is still a VC, meaning that its modus operandi is to make relatively safe bets that are expected to materialize with ~10 years. They never promised to make humanity's really hard and important problems their main focus. At best, they might be bold enough to allocate 1-5% of their funds to those hard bets, and that's already impressive and net-positive. To fund basic research, we need a direct and explicit commitment from the government or big foundations like Gates.