> we're entering a more hardened era of software
This is one force that operates. Another is that, in an effort to avoid depending on such a big attack surface, people are increasingly rolling their own code (with or without AI help) where they might previously have turned to an open source library.
I think the effect will generally be an increase in vulnerabilities, since the hand-rolled code hasn't had the same amount of time soaking in the real world as the equivalent OS library; there's no reason to assume the average author would magically create fewer bugs than the original OS library authors initially did. But the vulnerabilities will have much narrower scope: If you successfully exploit an OS library, you can hack a large fraction of all the code that uses it, while if you successfully exploit FooCorp's hand-rolled implementation, you can only hack FooCorp. This changes the economic incentive of funding vulnerabilities to exploit -- though less now than in the past, when you couldn't just point an LLM at your target and tell it "plz hack".
While agreeing, it also changes the mathematics of it: if a bad actor wants to hack me specifically now they have to write custom code that targets my software after figuring out what it _is_. This swaps the asymmetry around: instead of one bad actor writing an exploit for all the world (and those exploits being even harder to find), you have to hate me specifically.
Admittedly, not hard to do, but it could save some other folks.
Typically when hand-rolling code you implement only what you require for your use-case, while a library will be more general purpose. As a consequence of doing more, have more code and more bugs.
Also, even seemingly trivial libraries can have bugs. The infamous leftpad library didn't handle certain edge doses properly.
For supply chain security and bug count, I'll take a focused custom implementation of specific features over a library full of generalized functionality.
>there's no reason to assume the average author would magically create fewer bugs than the original OS library authors initially did
Have you read this old code? It's terrible and written with no care at all to security often in C. AI is much much better at writing code.
If I hand roll my logging library, I unlikely include automatic LDAP request based on message text (infamous Log4j vulnerability).