I'm writing mine, I'm surprised there are only two IMDb reviews of Garfunkel and Oates, and both those reviews are by people who either didn't pay much attention to the single episode they watched or they think "to critique" a show means "to criticize" it. It certainly is OK to criticize a show, if you watched it with an open mind, and actually watched more than one episode.
For one thing, how could anybody have actually watched more than one episode and think, "most of the jokes revolve around them being 'super bad at sex.'" Doesn't matter what a joke is about. What matters is it being funny. Riki and Kate are funny. Even in the pilot episode, there was a lot more going on than a single subject joke. Garfunkel and Oates is humorous fictionalized personal anecdotes and social satire. Those reviewers who didn't understand the pilot episode wouldn't understand any of the others, so it's a good thing for them they've stopped watching.
Riki Lindhome and Kate Micucci are not yet on the level of Marc Maron, Louis CK, or Amy Schumer, but they're getting there. Instead of stand-up before, after, or during their half hour skits, Riki and Kate use song parodies. The songs are short and humorous and always have something to do with the theme of the episode.
"As for the ukulele." OK, where are all those other ukuleles I've read complaints about? I watch a lot of TV and I've never seen any recurring character playing a ukulele except Kate Micucci as Shelley in Raising Hope. Actually, I've never seen many characters in recurring roles play any type of musical instrument.
Garfunkel and Oates is a lot better than the nitpicking contrarians will have you believe. Give it a chance. Entertaining, insightful, and funny. You might even learn to appreciate the ukulele, or maybe even get one of your own. You might not like Garfunkel and Oates, but those negative reviewers are grossly misrepresenting that show.