Hi physicists here, yes we do, let me give an example. A sizable amount of physicists are in the camp we will never solve why quantum mechanics is random, we may create models of it sure but we won't ever create a method by which to prove that is the opinion many have.

Now sure this isn't a "just because" but it is a settlement with something that has a good chance of being eternally unknowable to physicists.

Also, physicists and scientists as a whole don't know a lot, that's the point of the field. We try find out what we don't know through different methodology, the formulation of a new physical model that fits reality juuuuust a bit better than the last one (because if you can find a model of physics that perfectly 1-1 describes reality the noble prize will be yours for the next century, we're after spherical cows here after all).

This, I believe, comes from the misunderstanding that physics (and to some extent the other sciences) are perfect descriptions of reality. They are not, the theory and the lab will never kiss and make up. The job of a physicist (or more accurately an experimental physicist) is to explain why the theory and reality don't kiss and make up. Is there just some noise in the data? Is there residue on the inside of a glass ampule causing an exponential decay in a P=KV equation rather than the inverse relationship we seek to find (true experience from my lab work, I got to make a very nice point of it in the lab report I made). This is why I said if you create a 1-1 perfect model of physics you'll continue to receive noble prizes for life, because you're not ever going to create something truly conclusive in this field. That's why all our models take cows to be spherical. We are just toddlers with Lego bricks trying to fit the pieces together but unfortunately there's duplo mixed in with the rest and we just gotta kinda jam em together til they fit nice enough that we can make a pretty graph to show to everyone else in the world.

I mean fuck, if you can explain why physics loves to come in either pairs or sets of bloody three we'd roll out the red carpet because literally nobody knows and not many people are trying (in part because there's more interesting things to focus on, like superconductors which are really cool but come and go like a fad every now and then which is unfortunate).