I was just about to post the same thing. Plywood wouldn’t last that long.
Out in my garage I have a boat called a Whirlwind. It was made in Cockeysville Md. in 1958. It is molded mahogany plywood. and its as good today as it ever was. Of course its garage kept ,,to keep te sun off the varnish and I only use it 4 or 5 times a year and its only 16 feet. They were tough little boats and beautiful. They stopped making them in 1962 when fibreglass took over.