What is progression towards the equinoxes? You mean precession of the equinoxes? That takes millennia and is very much negligible when reading sun dials on a day to day basis, or even year to year basis.
The orbital motions of the objects in our solar system is pretty messy and you are right that there goes more into designing accurate sun dials than just a stick in the ground, but I'd still argue that that's not part of "reading a sun dial" - which was the question I answered.
"Old technology" like, hammers, spoons and books 🤣 Let's get rid of the wheel. That crap was invented ages ago.
Update: and if you can't read a sun dial - which by the way is just reading the number the freaking shadow points at - the US should seriously consider teaching stuff like that again.