On the flip-side, when I learned Autocad, I customized the interface to be more efficient with my workflow - I worked significantly faster, probably saving 20-30 minutes a day by having my quick-access macros, etc.

Then I went to another location and started trying to work on a colleague's Autocad interface, and I was helpless - I had never learned the default command set, I had to describe to him what I wanted to do (like he was ChatGPT or something) so he could make it happen. Over the next year, I retrained to use the default command set - and because I was using it less and less the time-loss was becoming trivial at that point.