Is this enough to be considered dry rot on my tires?
 

Lol. You're fine.

dry rot is a common term but is incorrect. that is what is called 'ozone cracking'. the photo above is 100% fine. even more sever cracking is acceptable, as long as the cracks are not deep and severe enough to see the sidewall threading construction.

ive seen newish tires only a year or two old have cracking like that, and 15 year old tires that look showroom fresh. it really depends how the tires are driven, where they are stored, if they are in direct sunlight or in a garage, if they have tire shine or other stuff applied etc etc.