The South has dominated hip-hop for more than a decade now. This can change, of course, but I have reasos to doubt it
1) Something that is overlooked is the purely demographic aspect of things. Hip-hop started in New York, then spread to other major urban areas, which made California the logical next place for it to blow up, but the place with the largest African-American population has always been and still is the South. So it was only a matter of hip-hop becoming as popular in the South as it had become elsewhere for the South to become the dominant region simply because once its popularity was equalized everywhere, the South would be the place where most of the talent would come from. For purely demographic reasons, as I said.
2) We live in the post-regional era of hip-hop now, with regional styles becoming extinct, except for trap music from the South which is dominating for the above-mentioned reasons. This makes it both easy and extremely difficult to establish new styles. It is easy because every up-and-coming artist has exposure to basically the whole world through the internet so if they come up with something new and original, they can create a following. However, in the same time, it is very very difficult to overturn the established style, for the same reason - because thousands of other artists are making music in the dominant style, and that's a huge momentum to be overcome for anyone on their own. Back in the days it was quite different - someone would come up with a new style, then only have to get it established in their local area, which is much easier task than establishing a sound nationwide or worldwide. And once a local style was established in a given area, there was a large enough local scene that could carry that style nationwide if some artists were picked by a major label and the style caught on. That intermediate step does not exis any more so while everyone can create a small following it is difficult to see how a major change could happen soon - it will have to be someone coming up with something truly revolutionary. The artists mentioned by the OP are mostly washed up, I can't imagine them in that role.