It definitely did for us. We went to one school with no summer school and there were a bunch of retirees on campus doing something and no students. My D22 struck it right off her list, but ultimately I don’t think it was a good fit for her anyway.
I wouldn’t worry about summer visits too much. This is for a junior? I would say you can always apply and come back and visit when school is in session if accepted.
If you feel like you have to visit in summer I would prioritize visiting bigger schools that have a robust summer school program. Those small schools with no one on campus are just sad.
I’m in NC. What schools are you thinking about here? I can tell you do not go to UNC-W in the summer. That is the one that my D22 was like nope nope nopity nope on after a summer visit.
You can also visit on Fall Break.