It'd be very difficult and expensive to revive any of the Apollo-era hardware. The tools and dies for that hardware were broken up long ago. Furthermore, you'd end up reengineering a lot of the systems because those 1960s vintage components are no longer available. For example, I doubt if any of the logic chips and integrated circuits used in Apollo are manufactured any more. You'd have to develop all new flight avionics. Furthermore, unless you want to keep trained CM pilots on board to handle the reentry, you'll have to develop autonomous reentry flight control systems. None of that is cheap.

The CRV is designed espressly for the escape mission. All of its systems are designed for long-term on-orbit storage. The flight control system is simplified to the point that a crew can pile in, close the hatch, strap in and press a button to come home. That's important for several reasons. First, you don't have to keep trained escape craft pilots on the ISS. Second, it allows for a crew that may be injuried or partially incapacitated by burns or smoke inhalation.

Given the ISS's 51 degree inclination, there are a lot of inhospitable places where an escape craft might end up landing. Good cross-range capability might make the difference from coming down in a jungle or coming down near a small city. Furthermore, Apollo capsules were wonderful spacecraft but lousy boats. A high percentage of the time, they flipped inverted after hitting the water. Since the escape craft could end up coming down almost anywhere, it could take many hours to get rescue personnel to the capsules. Also, the CRV parafoil allows the CRV to land just about anywhere from a small town airport to a clearing. Apollo capsules had provisions to come down on land but it would've been a very rough landing.