The valve has probably blown a seal, due to the combination of age and high pressure, and it might be possible to simply replace the seal. I don't know how that valve might come apart (it might not be serviceable), but I'd first look for any obvious ways to take it apart to get to the seal, which is probably pretty common. That will be easier than replacing the valve.
Absent that, yes, you can remove and replace the valve. You could cut the PEX, which is the name of the type of tubing to which it is attached. But the PEX isn't very well secured in the floor, and so not super easy to cut with a hack saw. The best and easiest way, I think, would be to use a pair of PVC cutters, available at any decent hardware or plumbing store....something like these:
https://www.amazon.com/s?k=pvc+cutter&ref=nb_sb_noss
With a pair of those, one snip and the PEX would be cut. Alternatively, you could remove that metal crimp band.....a pair of needle nose pliers or even a flat screwdriver to get in under the bent crimped part of it should loosen it up, but be careful not to gouge the PEX in the process. Once it is loose enough to slide up and down, you should be able to pull the valve out.
In either case, yes, you can replace it with a Sharkbite valve. It simply slides on the PEX, and you're done. No tightening or tools needed. They made be hard to find, so you could also get a Sharkbite fitting that connects to the PEX on one end, and then has threads on the other end for a pipe or PVC connection. There is also this Sharkbite connector that has PEX on one end, and then accepts PVC pipe in the other, so you wouldn't need a threaded PVC connection. See
https://www.sharkbite.com/products/p...ition-coupling
Dave