A quality mount will be physically adaptable, but most importantly, be able to prevent handling noise, cable rattle, etc. from reaching the microphone. This transposing process can be likened to the suspension of a road vehicle where the disturbing bumps and jolts are turned into a long soft floating rise and fall. The deeper the give, the smoother and quieter the ride. Typically, however, it is not shock that is the enemy. Well, so much for that take.
Shock is rare.
Vibration from handling rub and cable rub is the usual culprit. In olden times when ribbon mics were the norm, springs were necessary - to protect the sensitive ribbon from physical damage. This is not so with the modern, taught, mylar diaphragm. Now, many modern isolator materials are 'noisy' for the same reason. Press the tip of your finger against your ear.