Just as sensible for logistic reasons. If you look at the list of aircraft types they operate the spares and engineering support must be horrendous. let alone keeping aircraft like the F-14/F-4 flying with sanctions.
Rationalising fleets down to only 2 or 3 types and variants thereof such as the Mig-35, Mig-31 and SU-30/35 would only make sense.