GMO's trace back further than that - even when we're specifically talking about modern methods. The first Drosophila melanogaster fruit fly genetics experiments happened in 1910, though it took a while for us to begin actually creating GMO strains; the first study I know of that did so was in 1927 by Hermann J. Muller, using x-rays to purposefully induce mutations. But ultimately, it doesn't matter who was the first to purposefully modify the genetics of an organism, modern or otherwise.

The fact of the matter is that we can use, have used, and should use genetic modification for beneficial purposes. Again, GMO's are neutral; it just means an organism was purposefully modified on a genetic level by humans - it's the purpose itself that determines whether its good or bad. People will use it for bad reasons just like any technology, and we should stop them, but that doesn't mean we should shun the technology itself when genetic modifications have been used beneficially for millennia, and modern techniques are just as capable of producing incredibly beneficial changes as they are the detrimental ones everyone's scared of.