It is just cosmetics anyway, the glue is stronger than the wood and many '60s Fenders are 3, 4 or 5 part bodies. The famous early '80s reissues often have 3 or 4 part bodies and reach astronomic prices on the used market.
Two and more piece bodies are from an engineers point of view preferable to one piece bodies... The later could warp easier.
This said: when I bought my first halfway expensive Yamaha bass in the late '80s - a BB1100s - I was dissapointed and kind of felt betrayed after I found out that it had a 4 piece body. Back then I thought at least all US made Fenders would have 2 piece bodies.
I remember a story about Fender's US reissue of the '75 Jazzbass in ash: an artist complained that it had a two or 3 piece-body and Fender sent him a one piece bass back.