Very Discouraging- But problem solved

I disagree here.
The FPS counter from the Developer mode is the only way to find out if you’re limited by the main thread, or limited by your GPU, which helps in optimizing your settings.

Anyways, I made a request for this in the Wishlist, anyone here feel free to add your vote or comment:

Move FPS monitor from Developer mode to base sim - Self-Service / Wishlist - Microsoft Flight Simulator Forums