Playing Devil's Advocate here, looking at the stats and a documentary or 2, these airplanes actually seem quite similar in terms of roles.
F-14
MiG-25
MiG-31
The F-14 and the MiG-31 in particular were both known for being able to track and engage 6 targets simultaneously, all 3 are categorized as Interceptor/Fighters and were used for similar roles. What could the F-14 do that the MiG's couldn't, and vice versa?
This documentary about the MiG's claims the MiG-31 is more comparable to an F-22, but I think they are really more comparable to a Tomcat.
From MIG-25 to MIG-31 (Documentary)
Frisco1522