IIRC Russia is at 99% air defence effectiveness vs the start of the Ukraine war; i.e. it has not been materially degraded at all, despite HARM anti-radar missiles and so forth given to Ukraine.
Though I don’t full agree with Russia only using ground based air defense as the few newer generation jets Russia have are shooting down a lot of Ukrainian jets. They fly higher, faster, and can both lock and engage Ukrainian jets before the Ukrainian have even detected them.
I think that the USAF will have its hands full overcoming Russia's A2AD environment, assuming it's set up and competently managed. The range on S300/S400 makes it hard to use anything other than Tomahawks and stealth aircraft to target. It definitely won't be like Baghdad during DS.
[1] https://www.thedrive.com/the-war-zone/first-marine-corps-tom...
- old C versions from early 90s - only working on pre-programmed target mode - no targeting pods like AN/ASQ-213