Yes and people are paying top money to Canonical and RedHat to maintain these software don’t you think? They have huge enterprise contracts

Money alone makes poor filler material to patch such holes. Microsoft famously doesn't make their stuff for free, and yet somehow Windows systems have gained this reputation of having holes such that a train can go through.

People build trust, take shortcuts, cut corners all the time. It's how we are wired. Doing otherwise is an energy sink for our bodies. We don't make ourselves overspend energy when we can.