SFB we're sorry, you are correct… PhotoShop is widely acknowledged to be very very poor indeed. 🙄
Those
elementary user interface faults
have been painstakingly developed over 20 years and are industry-standard. Perhaps you should allow your trial copy to expire and think about alternatives.
Do you apply the same awesome rationale to all things new… wade in with the criticisms without even trying to learn for yourself – or think about why things may have been done a certain way?
Useful answers have been offered. As has been said, RTFM and set up an action if a 25 second investment to save 100 files is too much.
"Save for web" comes up with a warning because (above a certain size of image), you are trying to use the function for a purpose it is not designed for. It's an optimisation tool. I would suggest that if you've not yet got to grips with the fundamental difference between a .jpg and a .psd you are not really ready to touch on this. Walk before you run. How about you stick your nose in a tutorial for half an hour and learn something?
It comes across as extremely rude to ask for help then pooh-pooh the responses you know.