Nature might give efficient solvers for specific problems up to a certain size, but we already have "practical" NP problem solvers in classical silicon in the form of SMT solvers.
They're out there, and practical for some problems, but SMT solvers aren't exactly a solved problem. They're used for deductive proofs about program correctness, which are still pretty finicky. [0]
[0] https://blog.adacore.com/using-spark-to-prove-255-bit-intege...
That's the idea behind DNA-computing, for instance.
The question is whether it is actually possible to do so at a reasonable cost and at scale.
Regardless, what "nature" does has 0 to do with P vs NP, computability or anything else. P vs NP is a statement strictly about mathematical objects, there is no notion of "nature" anywhere in it.