Rusty wheel studs and nuts?

I have a 2020 Tacoma and yesterday I changed the oil and rotated the tires. I was able to remove three wheels with no problems. When I got to the right front it required more effort to remove the wheel nuts and once loose they wouldn't spin freely. After I removed them I saw that the studs and threads inside the nuts were rusty. I live in SoCal so I don't have to deal with road salt, I don't pressure wash my wheels, no offroad water crossings and I always use a torque wrench. Out of the dozens of cars/trucks I have owned this is the first time I had ever seen this issue. I cleaned everything with a wire brush and reinstalled the wheel. My question is what happened (why only the front right wheel) and how do I prevent it from happening again? Thanks in advance.

 

www.gibbsbrandlubricant.com
Amazon has it.

 

Some say you shouldnt use a lubricant on wheel studs because it effects the torque settings which can lead to over tigthening. Others say lubrication is essential to provide rust protection and prevent frozen/stuck wheel lugs. If lubrication is used your supoosed to reduce the amout of torque used to tighten the lugs. I am not sure I feel comfortable with this. I may just torque dry to factory specs and just keep an eye on them.

 

I spray the lug studs with a little wd40 to displace any water and prevent rust. 40k miles later and no problem.