I like this post. When you get past 10 years experience, you will have gone through phases of technology. Who is going to put "expert" for PHP 2023? Few. How about "expert" for Excel/VBA in 2023? Fewer. (Perl from mid-2000s!) Yet, 10-15 years ago these were important languages and ecosystems; today, much less.

I just saw a new hire at my company introduce themselves by email as a "senior developer" with two years experience. After reading that email, I cringed all the way under my desk...