Sorry to hear from your encounters
I guess it is really hard to put a number on steering rack lifespan.. There are certain models with higher reported steering rack issues like Civics, certain Honda models and F30s with low mileage while some are just fine after more than 10 years. It also got to do with design issues and the way owners driven their car.
My previous VW has clicking sound and knocking sound underneath the car as I go over uneven roads. Got it refurbished instead during 8th year of ownership (120,000km). Not life threatening, just annoyed by the sound coming from underneath the car.

D S Auto Enterprise Sg Buloh
Initial quote was RM880 but turn out to RM1500 as VW's steering rack is a combination of EPS and hydraulic, a bit more complex for them to do.
This was 2021.