As the previous poster mentioned, wood would only be used for particularly large poster type, but (if I recall correctly) even at large scale the printing press

As the previous poster mentioned, wood would only be used for particularly large poster type, but (if I recall correctly) even at large scale the printing press does wear out the wood blocks more quickly than metal type; the good designs that you see in wood would anticipate that distortion without compromising legibility. Wood type was also often very trendy, insofar that new designs that were bigger and bolder were developed and produced quickly — the aesthetic lifespan may not have been longer than the physical one.