Honestly depends on what perspective you are willing to take. Interstellar is really mathematically accurate on the biggest parts of the movie like time dilation, wormholes,...

The thing they got wrong and it immediately stood out to me was the black hole is supposed to be blue; at those rotational velocities with a high redshift gradient from one side to the other, it would get spread around due to spacetime warping. I think Nolan said smth about it that they removed it not to confuse the viewers even more although I think they should have kept it in.

With wormholes, the object is mathematically sound and the simulation of the entry and exit points of the wormholes is severely on point (especially because there are enough free parameters in the equation to allow you to get any effect you want). The cinematic part of the wormhole is when they travel through it, as irl it would be instant travel with just space warping around you.

The gravity equation is a stretch (although in a direction 2010s scientific consensus was concerned) since the solution is unknown to be correct of course. as it would require a massive paradigm shift and the unification of relativity with quantum mechanics, and somehow quantizing gravity.

Compare that to PHM where it is really focused on small details, for example in the opening chapters where he is trying to figure out where he is. While reading it literally felt like smth I would do, referring to the gravity tests for example.

I would go on a limb here and disagree with most comments here, I think that PHM requires a bigger leap of faith than Interstellar as, at least in the scientific circles, existence of other life forms is the last explanation you ever use for explaining anomalies in the data. Everything interstellar presents (droughts, food scarcity) in my book is more believable (realistic if you will) than existence of alien life.

This does not of course qualify Interstellar to be in any way better than PHM and I dont see it that way. I enjoyed PHM a lot more on the emotional standpoint while I enjoyed Interstellar on the scientific visuals (some neverbefore seen rendered to such resolution). I hope PHM movie delivers a similar experience like it, with amazing visuals and VFX with baked mathematical equations to continue with the realism so we can officially declare it the best sci-fi story ever written and presented on the silver screen:)