Since the release of Dragon Ball Super, it is confirmed by Akira Toriyama and Toei that Dragon Ball GT is non-canon anymore. But I was wondering if there was still some elements of GT that have maybe been kept by the author and which would still be considered canon in the actual Dragon Ball Super manga/anime, and notably the Super Saiyan 4 transformation achieved by Son Goku and Vegeta.
I do know that the events that led to those transformations are not present in the real series timeline, and so that they would not be able to transform in SSJ4 right now. But did Akira Toriyama confirmed the fact of totally ruling out this transformation?