I was searching for a solution about this. SciPy is translating everything from Fortran to C. https://github.com/scipy/scipy/issues/18566 . Sounds a bit too ambitious though it looks like they are almost done.

Anyways, ARPACK is in that list marked as completed. From the description the code is now thread safe but using it, is a bit different than the fortran version according to the readme file.

https://github.com/scipy/scipy/tree/main/scipy/sparse/linalg/\_eigen/arpack/arnaud