I have a cottage that was built in the 40’s and was very well kept by the prior owner. However, the prior owner took this nice shingle style cottage and buttoned everything up. He put in new windows and vinyl siding. Worse than that, he boxed in the soffits with plywood and then wrapped that in vinyl. In fact, he even caulked things prior to wrapping in vinyl. This is a recipe for ROT.
A lake environment can be very damp and humid. Because of that, air flow is critical. The photos below show what happens when something that should be open is sealed up.