Yup. And my feel on that is that (assuming the perf issue is related to a core data structure), that -particular- perf issue shouldn't even have happened in the first place. It should have been obvious given the right background and you could have spent that time doing something less fundamental.
Do you have to reach out for google or a book to do a simple if/else statement? What about a for loop? Now what about the difference between a map and a set? Likely not, it's the basics used in any app.
Talking about premature optimization here implies there's some work to be done, things to think through, stuff that's not obvious. And that's totally true at a certain complexity level.
But what is "complex" and what is "obvious" isn't objective. It's purely a factor of what the "average software developer" knows.
What I'm arguing is that while at one point the pendulum was swinging too far one way, it's now too far in the other, and it's affecting software quality industry wide.
As a software developer I see myself mainly as someone who solves problems to help others do their work better. So, while I agree that having a strong CS background is definitely a benefit, I don't think it matters that much if you can't get binary trees just right after not needing to implement them for years.