I agree with your point: something doesn't become a "problem" in physics unless it's so hard to find observational evidence that favors one view over another that it can't be quickly resolved.. So the remaining things left that count as problems are the very ones where different experts can reasonably hold different views, and one will see a stronger case in schools that support a particular view.

On the opposite end, problems in philosophy that actually get solved are then spun off into other fields and so no longer count as philosophy. What we now call "physics" was at one time "natural philosophy".

Still, I think there's a difference in that philosophy hasn't been spinning off productive scientific research programs in the past few decades. But don't think that was Daniel_Burfoot's point.