Are you suggesting to lower your FTP to match your “indoor” ability?
If so, that is the wrong approach. You will not be pushing your body enough to really get the desired adaptations.
You should be looking at the reasons you have such a disparity between inside and outside.
- Cooling
- Position
- Motivation
Look at these and others and make darn sure you are doing everything in your power to eliminate those from being restrictions or limitations to your power output while inside.