Recoil buffers are a solution in search of a problem.
I think the people who use them believe they will protect the frames of their guns from battering due to recoil -- but modern guns aren't damaged by recoil (i.e., the base of a guide rod slamming the frame.) The base of the guide rod is hitting one of the strongest points in the handgun; it's built strong for that purpose.) There may be some exceptions to this general statement, but generally, guns are designed to function without them, and adding them does nothing but add extra complexity and opportunities for problems.
Buffers may change the shooter's EXPERIENCE of felt recoil, but they don't really protect anything in the gun. 1911Tuner, who participates here from time to time, has demonstrated this very practically by actually shooting 1911s without guide rods and recoil springs; nobody gets hurt, and the guns are not damaged.
As Tuner notes in his discussions, the primary purpose of a recoil spring and guide rod isn't to control or manage recoil, but to cause the gun to cycle and load the next round. The force of the recoil as it affects the gun is not something likely to cause it damage, but if you don't contain part of it and reuse the force, the gun won't be able to fire the next shot.
When I first started shooting, one of the guns I bought came with some Wilson buffers, and used them. I found that they deteriorated very rapidly and, if I wasn't paying close attention, the pieces could get into places where they shouldn't, and cause function problems. That ws my first and last experience with buffers.
Recoil systems -- devices intended to change the recoil impulse -- are sometimes used, and they may have their place in shooting. But, they help the shooter, and aren't intended to protect the gun.