I think they can be on topic, but the questions I've seen seem to be kind of trivial and superficial. Example question "What goes good with British style dinners" titled "What's a good beer to have with steak and potatoes?"
I think for it to be a good fit on the site, it should be a little more specific with menu and goals. Take steak... Filet? Porterhouse? NY strip? Ribeye? Sirloin? Seasoning?
Along with that, the "what and the why" of it. I found this example answer on beeradvocate:
I recently paired homemade chili with Stone's Chipotle Smoked Porter.
I'm sure the regular and the vanilla versions would work as well, as the mix of smoke and malt (in taste and texture) were the key components in complementing the spicy food. However, I found the chipotle added a nice roasty heat, so while it quenched your thirst after a spicy bite like a glass of milk might, it imparted just a smidge of heat in the aftertaste to segue into your next chili spoonful... I was surprised a chili and a porter could provide a real pairing experience, akin to a wine pairing.