Squeaking can certainly accelerate wear.
A squeak is a resonance were 2 parts are rubbing against eachother in a pulsating movement where peak pressures on the material are higher than were it a smooth manner.
Squeaky steering noise can also come from the steering rack where the outgoing rods are in need of lubrication. With no lubrication and squeaking over and over the tolerance between rod and slidebearing can increase resulting eventually in a situation that extra grease won't work anymore and then you need to replace your steering rack.
Too little lubricantion on those outgoing steering rods results in the 'foghorn effect', like you can hear in the video below
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