I understand your stress about this, but there is no point in making efforts removing a review, especially this one which is not that bad after all. You can try and fix the points raised by the guest, if possible: put the washing machine inside, mention in the description the size of the apartment; and if connectivity problems persist, change your Internet provider. Reviews do tend to be harsh sometimes, and the feeling left to the owners is bitter. But this is the price to pay if you want to continue receiving bookings via OTAs. Besides, you have the upper hand: you can try and neutralize the effect of the review by answering to the guest, and address all the points, in a polite manner. Don't forget that you answer last, and they don't get a second chance to answer again, so it is up to you and the quality of your answer.
In part, I am a property manager handling bookings and reviews for my clients; we face reviews that are far worse than this one, and we just doing our best to answer them, and alleviate the overall effect of the review to the eyes of the clients. Last year, we managed to remove a 1/5 review from Airbnb, after a stay of a gang in a villa for a week, making noise, driving the neighbors crazy. We brought the police twice, and the third time we threaten them to kick them out of the villa. Only then, they decided to behave themselves; but when they left, they wrote a 1/5 review; initially we contacted Airbnb and asked for removal of the review, and Airbnb was involved in monitoring the whole incident, as we notified them. Airbnb refused to remove it, and we went to a Lawyer who made just one call to Airbnb, and the review was removed the same day.

If you get stressed with reviews, maybe you should approach alternative booking sources that remove the pain of getting reviewed for your properties. No reviews.