Any mechanical device is going to require some sort of maintenance, regardless of any advancements made.
For example, back in the day it was recommended to change automotive oil every 3k miles or so. Nowadays new cars can run 8k plus between changes and most good synthetic oil is rated to at least 15k.
But it still has to be changed.
To bring it back to guns, the 92 and clones are a 1985 (give or take) design and basically beholden to the same limitations of an '85 civic with respect to regular maintenance.
Just because this frame or that frame has better longevity between maintenance periods does not equate to maintenance free.
I've had my 92fs since 2012, maybe a little longer. I think I may have just passed 1k rounds, with plenty of +p in that count and I still have plenty of paint on the rails and my locking lugs are barely shiny.
Would a steel insert increase longevity? Maybe, but since the design was never intended to feature this, manufacturing one would start off a whole new set of growing pains. If you want a steel insert, I believe the new SIGS do this. You just swap the firing unit to whatever frame you want to use.
The 92 was never designed for this and likely couldn't be produced that way at a reasonable price point. Accept the limitations of the platform.