AFAIK, it will utterly destroy many of the volatile components of wine that make it taste so complex and interesting. That's why alcohol-free wine tends to be so bland and uninteresting.

I'd be willing to do a taste-test on alcohol-free wine vs wine that I already know that I like... If you hide the non-alcoholic one in sufficient number of normal ones I probably wouldn't guess which one it was (I'm not good enough at telling which wine is which that I'd spot a particular wine by taste, just whether I like them or not).