> How did we get to the point where there are a thousand privilege escalation exploits in the kernel?

Local privilege exploits have been accepted as being there in Linux ~forever. The past 10-20 years with containers, people have tried to kind of ignore it or pretend it doesn't exist. Nobody with any serious security concerns would ever put untrusted users on the same box, containers or no. Virtual machines are where there is a bit more effort to take this seriously.

You could quibble about complexity and architecture and language but I think at the end of the day it's primarily about incentives. There is not much incentive to make this secure.

I don't know if you would assume all software is more compromised, but you should assume that all software development follows incentives similarly.