I have an 1983 Pearson 34 and it is cored below the waterline. All of the thru-hulls are mounted in solid glass areas so that if one were to leak it can not get into the core. The survey did not show any wet areas at all. If the hull is dry, there is not a problem in my opinion.
Mr. Pascoe certainly does not like cored hulls. Of course, most of his disparaging articles are about powerboats and hulls whose outer skin is not thick enough to withstand the pounding those hulls take plus the indiscriminate drilling of thru-hull holes without proper treatment to protect the core.
I would bet my Pearson is better constructed than a SeaRay, but that's just me.