One has to be careful with substances these days. I have a pump bottle of hand sanitizer and hand lotion in my van, to decon and as needed re-hydrate when I enter the vehicle ... and neither of them are any good for steering wheels. So I have to sit around and wait for my hands to be dry before driving off, or dry them on some paper towels.
Careful use of leather cleaner and lotion can help with longevity of the wheel.
I have never quite had an issue with any of our vehicles, up to 100k miles. Then inevitably, some of the leather will start to deteriorate between, sun, driving, ...
The thing to absolutely avoid, is what my wife did one time, thinking the steering wheel was vinyl and use some random detergent and a scrubbing pad ... because I had done a bit too much work in the field and trimmed too many trees, without washing my hands. :'(