This is true. The real question is, how much environmental protection (EP) is needed to get full protection against acid? Five, maybe? Steeltoed boots (EP=3) still allow damage. Also, must not forget Hazmat Suit and ANBC Suit. Full coverage, high EP. Most likely you’ll only need boots that have high enough EP. I’ve never taken acid damage anywhere else than to the feet. In that sense, the rubber boots might be superior footwear!