I generally hate it, but I think it depends upon the franchise.
In something like Marvel, it makes sense, since you're dealing with literal superheroes, which stretches plausibility to begin with. Plus a lot of the stories are based on Earth, which sets the scope a bit smaller.
I absolutely loathe it in Star Trek though, because the actual setting is not a single planet, but a wide swathe of the galaxy. There should be thousands of inhabited planets, each with billions of people. There should be tens of thousands of different ships in each fleet. Having the same folks run into each other randomly just doesn't make logical sense, nor does being the "only ship in the quadrant." Though Trek has typically fudged around with this a lot, with "colonies" only having a few thousand people for some reason, and major players like the Romulans and Klingons never even having a canonical "second planet" which has a substantial population.
It also makes the setting itself seem small when it shouldn't. A great example is how the (generally great) DS9 dealt with Ferenginar. The show had Quark running in with the Grand Negus (effectively the head of a multi-stellar empire) on a yearly basis. Eventually his mom started dating the Negus, and his brother became Negus. Liquidator Brunt was also changed from a generic antagonist into someone with serious designs to control the Ferengi Alliance himself. As a result "Ferenginar" felt like a small village off somewhere, not a bustling capital planet of a multi-world alliance.
I'd also argue thematically it makes little sense to have Trek be a world of these great and renowned heroes. The Trekkian ethos is much more about talented professionals working to the best they are able as a group. It's a world of free will, not destiny. A world of meritocracy, not of nobles.