I don't think the scientific accuracy of those two movies can be compared. They don't work on the same level of abstraction.
Gravity is anchored in reality. It involves the space shuttle, the space station, Hubble, and astronauts doing spacewalks. Those all are real things, and before the space shuttle program was shut down in 2011, those sorts of things were actually happening in space. In a way, Gravity isn't even a science-fiction film, but rather a thriller, which happens to be taking place in orbit. When people complain about scientific inaccuracies in the movie, they do it on a very technical and detailed level. They say that the orbits of the stations aren't correct, that space suits would be pierced by high-velocity debris, that it's too hard to aim correctly when propelling oneself with a fire-extinguisher, and so on.
Interstellar on the other hand, operates more on an intellectual and speculative level. It involves the traditional tropes of inter-galactic travel, such as a worm-hole. No worm-hole has been observed for real. As far as we know, it's a mathematical object that is merely possible. The logistics of how a spaceship could travel through it belongs to the realm of the unknown. So when the movie deals with it, it does it speculatively so. And it does the same for various other themes, such as what is happening inside a black-hole, which is, again, unknown. Interstellar has been, as far as I know, mostly greeted with regards for its general scientific accuracy. The time dilatation near the black hole is spot on, much as is the visual representation of the black hole itself, thanks to the well-marketed involvement of physicist Kip Thorn in the creative process.
The comparison between Gravity and Interstellar seems very unfair to me. Since the latter deals with speculative scientific themes, it has a lot of leeway on how to deal with them. The only condition that it has to comply with in order to be accurate is not to include something that is known to be impossible. But since we specifically don't know much about the concepts it deals with, "not impossible" includes quite a lot of possibilities. Gravity, on the contrary, deals with very concrete and established scientific and engineering rules. In order to be accurate, it has to specifically chose the only path that is known to be possible, a single tiny deviation from that constituting a blatant inaccuracy. Where Nolan has a million possibilities to chose from and will take the one that appears to make the most intellectual sense, Cuarón must deploy a wealth of imagination to make something spectacular and interesting from inside a well-defined box.
Both movies leverage some level of suspension of disbelief. Interstellar involves matching the radial speed a of spaceship with another in the middle of a lot of debris; "gravitational anomalies" which make sand not fall in a consistent manner in a room; as well as writing Morse code on a watch from inside a black-hole. Anyone who has not a single plausibility problem with that has been the victim of a successful inception by Christopher Nolan (or should I call it the prestige of a magic trick?) In the end, the willingness to give a pass to those questionable things in order to continue enjoying the flick depends more on how you enjoy the general approach of the film rather than on how objectively consistent those things are (if that could even be measured).
In my case, I enjoy the Gravity approach much more than the Interstellar one. I think that Nolan has a tendency to leverage "Pandora's boxes" which, when opened, allow him to emancipate his creativity without much explanation. In Inception, the Pandora's box were dreams, where Nolan could provide different kinds of scenery and action without having to justify where they came from. In Interstellar, the Pandora's box is the black-hole, which, since we don't know how its inside work, can contain anything. I'm much more comfortable with movies having clear boundaries and trying to be as imaginative as possible within them, and that is the reason why I'm blind to most of the little problems in Gravity. I just like the concept, I want to enjoy it.
There is only one mistake I don't forgive Gravity for, and it is the scene where George Clooney drifts away after Sandra Bullock lets go of him. They came to a full stop prior to that, and, by virtue of Newton's first law, there is no reason he should have drifted away. This is bad because it is no logistical detail. It is a fundamental violation of elementary mechanics. A stain on a otherwise such great picture.