2010 right rear speed sensor replacement

I own a 2010 hatchback with 116k miles, garage kept. I have seen a lot of posts about issues with rear speed sensor, VSC lights, etc. While driving the ABS, brake and traction control lights came on and braking was affected. The dealer replaced the right rear speed sensor and wire. The service staffer indicated that in the Midwest salt and corrosion could have been the cause. I think it was going for a while before failure and have several questions. I was concerned about my safety.

It seems this is a common problem—is that true? Is it related to normal wear and tear or something that Toyota should do something about since it seemed to be a safety issue and affected the regenerative braking?
Could this have been detected during normal maintenance before failure?
Do i need to worry about other speed sensors having the same issue?
Of course it was not under warranty and was an expensive repair. I am considering contacting Toyota customer relations about this and would like input if this is reasonable to ask for some compensation. Has anyone done this ?
Thanks for any suggestions.

 

It looks like components included the hub &bearing assembly, wire &skid control wire and flange nut.

Nov 2018 112k miles I had rear brake pads, shims and rotors done. Would anything have been detected then during inspection? No notes on m6 service record..