Both these animators were hugely influential at Disney in the 1930's and both left the studio in the 1940's. Moore returned after putting in time with George Pal and Walter Lantz, but Tytla never returned. He went to Terrytoons as an animator and later moved to Famous Studios as a director.
What interests me is the difference in their experiences and reputations after leaving Disney as I think it illuminates something about their work.
Moore is famous for the appeal of his drawings and he maintained that appeal when his drawings moved. While he is associated with specific characters in the early Disney features (Dopey in Snow White, Timothy in Dumbo and Lampwick in Pinocchio), I think that his sense of design dominated his ability as an actor.
When Moore went to Lantz, his work remained recognizeable and continued to be appealing, even when animating characters as bland and formula as Andy Panda or the dwarf rip-offs in Pixie Picnic. While Moore was probably forced to work faster than he did at Disney, his work really doesn't seem to suffer much.
When I first read Disney Animation: The Illusion of Life, I resented how Thomas and Johnston treated Moore. In the intervening years, though, I think that I've come around to their point of view. When they talk about Moore not being able to keep up, I think it's a criticism of his acting. Moore was enormously talented, but his talent was a surface one. For whatever reason, he didn't get as deeply into his characters as other Disney animators were beginning to do.
By contrast, I think that Tytla's main skill was his acting. He was classically trained as an artist, so he was certainly no slouch in terms of his drawing skills. His Grumpy is really the only character in Snow White that undergoes a significant change over the course of the film and is the greatest acting challenge because of that. The emotional relationship Tytla was able to evoke between Dumbo and his mother is stronger than anything else in that film and would rarely be rivaled in later Disney features.
Leaving Disney, Tytla became a great actor in search of a great part. The kind of drama that he excelled at wasn't being done anywhere besides Disney. Whatever one's opinion of Terrytoons or Famous Studios, can anyone point to a genuinely great performance that came out of either one? It's not that those studios tried and failed, it's that they never conceived their films in terms of Tytla's strengths in the first place.
While Moore could conjure a great drawing out of nothing, Tytla couldn't create a great performance without a well thought out story, character and voice track to fuel his animation. Tytla needed a kind of support that no studio besides Disney was capable of providing. That's why Tytla's career was effectively over when he left Disney and Moore's was able to continue without suffering nearly so much.