I agree with a couple of the others, it looks like the leather got dried out. Seems like the cracks are more pronounced now because it soaked up the conditioner. I'm sure some of it is normal wear/tear but I would think it wouldn't dry out much unless you are using some type of a cleaner on them, or a hand sanitizer with alcohol in it.
The one picture from a distance isn't as noticeable, just in the close ups.