In psychological terms, he's saying he has a need to solve hard problems in order to validate his identity and make himself feel good. At some point in his past he experienced some psychological trauma, and this hard-problem-defeating became his coping mechanism.
"That satisfaction is why software engineering was initially so gratifying."
He became a software engineer to gratify his need to solve hard problems, to validate his identity, and make himself feel good. If he stops needing to engineer difficult software, there goes his identity, his self-worth, his good feeling.
"But recently, the number of times I truly ponder a problem for more than a couple of hours has decreased tremendously. Yes, I blame AI for this."
When he runs up against something that takes away this thing that validates him, he feels de-valued. Rather than recognize that AI is making his life easier, freeing him up from mental labor, he's experiencing it as a loss, almost an attack.
"If I can get a solution that is “close enough” in a fraction of the time and effort, it is irrational not to take the AI route. And that is the real problem: I cannot simply turn off my pragmatism."
Now this link of hard work with his identity is becoming a problem. He's going to feel bad because he doesn't know how to deal with his life being easier now. This is a reason to address it head on with therapy, and a re-evaluation of what gives him value as a person, so that having an easier life doesn't feel bad.