Hi Cal, I have loaded up a saved game and can confirm that I still can't upgrade my units using scrap after using the old option to unlock technologies so I think it's a good thing that the option was removed. I've tried to attach a short video to prove this but it doesn't appear your website likes me when I do that.
If people want the option back then that's fine (I just won't use it )
If you want an option for auto-resolve battles to win, you are probably going to need to request that feature and start a vote for it.
I know I'd vote for it if came up.