One. Can plywood be used for bathroom door frames?
No.
Thin wood particle board offers excellent screw-holding capacity, high strength, and features such as hardness, sound absorption, and thermal insulation. It also has a low moisture content, typically between 10% and 13%, and is easy to work with. However, thin wood particle board is susceptible to moisture damage, so it is not recommended for use in bathroom door frames, as bathrooms tend to have higher humidity levels than other areas of the home.

Two. Are plywood door frames a good option?
Okay. However, during application, it should be avoided in kitchen and bathroom areas.
Plywood is characterized by its excellent screw-holding capacity, high strength, rigidity, sound absorption, thermal insulation, stability, ease of processing, and low moisture content, making it a great choice for doors, windows, and frames.
However, plywood is susceptible to moisture, so using it for kitchen and bathroom door frames is not recommended.