I think that's very harsh @Kia272 . Ratings of 4.20, 4.30, 4.35, 4.50, 4.57 are not 'dismal' at all! (The 2* room had had only 1 guest and the 3.3* room only 3*, so one low opinion skews the averages, as we all know.)
We're talking BUDGET listings in a shared house, and a proportion of folk will always give those a lower star rating than they would a luxury place with elegant decor. - I get the impression that guests in the US are more likely to rate low for simple basic places with no frills.
Furthermore, some guests were highly complimentary, and there are some repeat guests. There will always be a few bad reviews for basic budget accommodation, from people who hoped for something flasher, but weren't prepared to pay for it!
Obviously where kitchens & bathrooms are shared, there isan element of pot luck regarding whether the other guests will be tidy & respectful of others or not... It's not the host's fault if fellow guests have low standards. You take that risk when you book a shared place.
I disagree that these places should not be allowed in the pandemic. They serve a need if that's all some guests can afford. You get what you pay for, and guests who understand that write OK reviews, appreciating they got value for money.