As for me, yes, I clearly understand my codebase less. I'm sure of it, I've noticed it lately. What I tell myself is that my value is less there now, and more in my ability to organize the whole thing, on the human side as much as the machines and tools. So I focused on what actually brings value to my company or my role, and it's true that code counts for less there.
I completely understand people who feel lost. A lot of developers chose this job because they were comfortable with code, not to do marketing or sales. And the job that's taking shape asks them to code less and organize more, that's the real tragedy of this shift. Unfortunately that's how the world works: adapt or die. Let's be clear, a lot of people won't make the jump. They'll see their job as dead and may end up leaving it. That's normal, and a shame.
But on the other hand, I think believing you can do without AI is limiting yourself, even a bit illogical. As imperfect as it is, refusing to use it is a bit like refusing the printing press when it was invented. Lots of jobs died, that's a certainty: everyone who wrote texts by hand. Honestly, I see AI exactly like the invention of the printing press. It deeply changes how we produce content, and we know we're going to produce a lot of it.
With the printing press, as with AI, we produce a lot of imperfect stuff, maybe even pointless texts. We already see it: AI often produces code that isn't secure and leaves holes. But flip the question: what valid reason would we have today to abolish the printing press? It produced millions of mediocre books, and yet nobody wants to go back to scribes, because it put the written word in everyone's hands. I think it'll be the same for AI. The real question isn't that it produces bad code, it's what we'd be willing to lose by refusing to use it.