If there are upstairs neighbors who are loud, you should disclose the possible noise factor in your listing. And you could also provide earplugs for your guests.
You are upset that the guest didn't mention this during their stay, yet say it's something outside your control, so how would them mentioning it have changed anything? Would you have spoken to the upstairs neighbors?
I agree with Emiel- it isn't a negative review at all. They have mentioned nice things about your place. It's fair for guests to also mention things which weren't to their liking. It's not like they went on some big complaining rant.
@Kenny56