Why do ppl like the angelic ring so much?

That explains it all.
If it can be pot'd, it becomes infinitely more valuable.
Remember, people are offering in excess of 3 times max mesos for the DAB recipe. A ring that can be 6%primary stat is probably more valuable than a 10att ring.

I put on a 6% str 2 str specs today. It was only 300 range better than my 3 att 3 all dragon glasses. If 3 att 3 all can come close to 6% primary, why would 10 attack not beat it?

It's first tier potential. At unique status it is not going to beat a level 17 evo ring.