Personally I wish I could program as low as I wanted to. I always have the urge to toss assembly in-line but too much of it leads to portability issues and when shipping a product we as developers like to avoid too much headache. In comes the commercial game engine market right? They solved a problem fair and square and lowered the barrier of entry. Which equals more and more independent games. Personally I program everything in C and nothing else but as mentioned here that's because I like to know how things work and it's fast, programmers like fast.
At my company we use custom tech only but that's because we don't rely on games as our primary area of business so we can. It is a resource strain otherwise. I've worked on teams that have used Unity but it's like driving a car with a blindfold to me.