According to the engineers at Boeing, and the flight-line old guys at St Louis (they service and repair the jets), the F-15E is 80% different from the Gay Eagles. Don’t even have the same landing gear. Totally different jet.
If you just go by looks as most non-aviation types usually do, then yeah, but if you actually look at the components of the jet it is not.
The F-15E is a terrific multi-role jet.