There is hope of improvement on the plywood front: since the formaldehyde used in plywood is potentially carcinogenic it is encouraging many plywood manufacturers to adopt low formaldehyde-emitting glues. Joubert now use low formaldehyde-emitting glue in their plywood which has Lloyds approval.

Polyester and epoxy aren't eco-friendly, but they will bio-degrade if not protected. So we paint and varnish it, which probably has more environmental threat than the resin.

One should do what one can. I don't use polyester resins. I use closely fitted joints to eliminate then need for non-gap-filling glues wherever I can and use epoxy only for externally-exposed joints below the waterline. I found a quart of epoxy was enough for 2 solo canoes and a small sailboat. No joint has ever failed on those boats, epoxy or other. I use ply so I don't have to glass my boats or encapsulate them in epoxy; I find a few coats of environmentally non-challenging paint sufficient protection.

I recently lost a boat to an internal glue void leading to extensive plywood delamination - a BS1088 stamp is no guarantee of anything these days even when the plywood comes from a trustworthy source.