Your baseline argument is wrong because you are talking about generic mini conflict scenario between two similar countries. Fine. But we are not facing some rando 3rd world country with few jets or tracking radars here and there. We are facing Israelis+US+NATO, not even RuAF can face them alone. Even when we fire a missile from Iranian territory, US AD assets on ground, sea, air, space, pick it from its ignition on TEL, search n track it, transfer real time data to Israeli layered ABM/AD shields who just have to shoot the exo+endo atmospheric interceptors for it (They failed against Fattah-1, Kheybar Shikan, Ghadr-F etc). IRGC had to strap in EW patches to MRBMs to escape bidcourse jamming by US sats after True Promise II . In this extreme hostile environment good luck sending a 4th or 4+ generation imported fighter to enemy territory or in proximity to such first world enemy with worlds largest defence budget and tech in its hand. That jet will be facing Massive EW attacks, Search-Track-Detect-Attack from TPY2, SPY-2 slaved THAAD, Iron Dome, PAC-3, hundreds of F-22, F-15E/I, F-18E/G, F-35I/B, all integrated. Back home its airbase cant stop volleys of 1000 Tomahawks or hundreds of separating warhead lofted apogee ALBMs no matter which AD battery you park near it. I have not even counted the internal quadcopter or ATGM terrorism they can cause because they have the money and means to use your own disgruntled population against you. 50-100 Million USD per airframe can turn into rubble on ground against such enemy. Also the same enemy, because they are diplomatically and financially controlling the most of the globe can cause hurdle in much needed spare parts for such planes. Even with ToT you need critical replacement parts to keep the fleet alive because outside superpowers nobody makes those parts. We saw what happened to our Shah bought worlds 4th largets fleet during war against Arabs when 450 fighters had no regular parts supply. You see the dilemma of launching fighters against such foe ? IRGCASF does not face any such hindrance, they have underground bases so they are not vulnurable and they can attack enemy with variety of missiles without fear of losing aircraft or people in air, a moral degrader. Hence its better to fund them instead of making mistakes that Baathist Iraq comitted of launching few Mig-21/23 against 500 F-16/18/15. IRIAF needs to be built but underground airbases are a must for us and so far we barely have 1-2 that can house 2-3 squadrons at most. The money and resources required to create 6 more such bases to house 8-10 squadrons of SU-35S will give IRGCASF 4-5 underground missiles bases that can launch hundreds of K-4 Post Boost Phase submunition IRBM to Fattah Hypersonic to Soumar Long range LACM. Even with this amount of money, the MIG-29 SMT, YAK-130, SU-30SM, SU-24MK fleet will still be sitting naked above surface.
What you are describing is true if we fight a regional enemy or enemies then yes but it wont work against US+NATO+Israel.
So far following missiles have hit enemy targets without getting shot, despite being fired in high numbers (last 5 years).
Fattah-1 Hypersonic MaRV-MRBM
Kheybar Shekan-1/2 high supersonic/pseudo-hypersonic MaRV MRBM
P-800 Oniks High Supersonic CM
Khinzal ALBM
Golden Horizon Separating RV ALBM
Rocks Separating RV ALBM
Blue Sparrow Separating RV ALBM
Ukrainians claim to have shot down few Khinzals but even if we go by their claim the % kill ration is barely 10%. Rest have not been touched despite facing THAAD, Iron Dome, S-300PMU-2, Khordad, HQ-16/9 etc. Attack weaponry tech has far exceeded the AD tech. If we dont adapt to changing warfare then we are doomed.