Earlier quoted context omitted.
Experience gained in the last 20yr in the middle east (Afghanistan in particular) indicates that what we traditionally consider "fighter" type aircraft are capable of delivering various guided munitions with sufficient accuracy and that time to location is highly important. Having dedicated CAS aircraft is nice and it's probably wise to keep something of that nature in service at all time but it's foolish to pretend…
This is the same type of argument that people make over programming languages or EMACS/VIM. You could provide CAS with just about anything that flys. However a good CAS vehicle should be able to fly relatively slow and be well protected from ground fire. The A-10 if perfect and I really wish there was a way to make new ones. I even heard at one point the USMC was thinking of bringing back the OV-10 Bronco.
The A-10 is a death trap in a modern air defense environment. The USAF hasn't gone against one of those since Kosovo, and even back then it was all high-altitude fast movers and stealth aircraft dropping ordinance because of the threat of Serbian AD.
What the A-10 is perfect for is counter-insurgency, which is pretty much all the shooting action the US has seen since Kosovo. There's an argument to be made that, considering US engagements, a dedicated COIN aircraft is a good thing to have in the US inventory. It's a niche, though, and the US military is currently resistant to fielding niche systems.