I think it’s great to go to college where you know someone. My D22 ended up transferring after her first semester to a school where a good friend a year ahead goes. She is much happier (it also has a stronger program in her major).
I sense from your post that you are worried her higher achieving friends are going to go off and leave her at U of Arizona and they are going to go off elsewhere. Well, that could happen. It’s true. If it does and she ends up at U of AZ while her friends are elsewhere then she will just have to make the best of it. You can’t make the friends go where they don’t want to go. There will be lots of other people at her college to meet.
My D22 was good friends with her roommate at the first college she went to and I think she still talks to her some, but she is happier at the second school and found a girlfriend right away. She gets together to cook meals with her friend from home, too, but she just met the girlfriend on her hall. Not anybody she knew from before.