You’re confidently making a lot of assumptions that don’t generalize.
For example:
> performance is not complicated
Not to mention all your assumptions about the motivations of people who don’t do optimization well. That one can’t possibly generalize.
I would like to half agree to this.
Saying "Performance is not complicated" is not wrong. People and the systems set up for an application make it complicated. Its harder to check and verify.
I work in UI performance and the biggest thing slowing me down is always people
They are not generalizations. They are frequently repeated observations. The ability to operate from evidence is what determines if you are working with real professionals or children pretenders.