Exactly. Even pressure-treated wood gets pockmarked relatively quickly with nicks and scratches. It’s not visible on wood since it’s already so textured, but a transparent surface would be rendered opaque.

That aside, the whole article reads like AI slop. This paragraph is particularly obvious:

Instead of refilling the pores with epoxy, the team soaked the cellulose layer in a mixture of egg whites and rice extract. A curing agent called diethylenetriamine was also added to keep the atrial see-through. Importantly, the team says that the amounts of the various chemicals and reagents used in the process were small enough to present a danger to the environment. According to the team’s statement, they were “left with semi-transparent slices of wood that were durable and flexible.”

It’s just a collection of four sentences without any real unifying idea. And the latter two sentences are complete nonsense if you really read them.