The current mobility GPUs from AMD are not really a match for Nvidia's lineup, but htat could change in a few months. Data mined from the latest macOS Mojave mentions a total of twelve unannounced Vega 20 and Vega 10 GPUs. Some of these could end up in Apple's upcoming MacBook models, so it looks like AMD might attempt a comeback in the mobility sector.
https://www.notebookcheck.net/Unannounced-AMD-Vega-GPUs-mentioned-in-macOS-Mojave-update.376716.0.html