Stealth is the only technology that provides any safety in a modern air combat environment. The F-15 is a wonderful aircraft, but it doesn’t have any stealth capability. That’s why the F-22 and F-35 are far superior to any Gen 4 fighter, including the Mig 29 and SU-27.
Only the US, Russia, and China have Gen 5 fighters. Everything else is just a target now.
The 35 Moonpig has some frontal stealth, but it’s far from a stealth. From 3/4th of aspects, it’s not stealth. Hang missiles or tanks on it, it’s not stealth. if it gets caught in daylight, it cannot prevail against an F-16, a MiG-29 etc. It cannot outrun, out accelerate, out turn any Gen 4.
22 is pretty dang good, but we only have 186 of them IF they are all operational that day. Most of the tooling to build new ones was destroyed. We have about 120 in an operational capacity.
Stealth is a losing game except in the opening days. Gen 4 and 4.5 is still very relevant. It is doomed to fail in the battle of airframe vs sensors.
And the Su-57 and J-20 with those stealthy canards are not in the same class. There are 22 Su-57s in service and a handful of 20s.
Our 15s are far from useless.