i think you could tell me it was bakelite instead of wood and i'd believe you

Or the Fallout timeline, where a global oil crisis (wait a minute ) means oil-derived products have to be substituted with alternatives like wood, or resin-based polymers like the ones the Soviets used IRL (like the famous "bakelite" AK magazines, which are technically made of a different bakelite-esque material), which give off a kinda wood-ish vibe anyway. The P90 is even in Fallout 2, so one could imagine a post-apocalypse gunsmith having to replace the original polymer stock with a wooden one after it was broken and there were no spare plastic parts to be found.