With the Rus giving Iran "up to" 24 Su-35's (Flanker E)...
https://www.zerohedge.com/military/russia-reportedly-supply-iran-24-advanced-sukhoi-fighter-jets...Israel will have fun downing these darlings...
...maybe in another 3 decades the Rus will share some Su-57 (Felon) 5th Gen, LOL.
This is only akin to selling F/A-18's, Rafale's & Typhoon's...and I would argue the F-15CX/F-15EX upgrade is a step up from these Gen 4.5 since the Strike Eagle variant already meets much of the 4.5 criteria.
Anyway...the race is on to 6th Gen and beyond the US has its NGAD F/A-XX program, Russia has their Mikoyan PAK DP (listed as Gen 5++/Gen6 due to unclear profile), China has another Chengdu that obviously has something planned but since their so-called J-20's are rarely sighted beyond static displays they could still be treading water (who knows?), India working on "systems" but unclear as to manned fighters, and the Euro's appear to be doubling up in some cases with UK, Sweden, Italy & Japan in on the FCAS-Tempest program and the France, Spain & Germany FCAS-SCAF program.