The high number of cards that passed certification doesn't imply there will be a lot of desktop cards. Some of these are likely notebook versions or cards for the compute market.
Unlike Vega 10 which was exclusive to the desktop, Vega 11 will be the first ever HBM based graphics card to come to notebooks. So a number of those 13 certified boards are going to be mobile variants. If things go according to plan for AMD, Vega 11 should be ready to go into notebooks in time for the holiday season alongside its Raven Ridge APUs.Take it with a grain of salt but the site also suggests the first two Radeon RX Vega cards based on the Vega 11 design could be the Radeon RX Vega 28 and Radeon RX Vega 32. The site isn't sure about the accuracy of these details but heard the Vega 32 could have 2048 GCN stream processors, a 1024-bit memory bus, and 4GB HBM2. The Vega 28 on the other hand is rumored to be a cut-down version with 1792 stream processors and the same memory specs. The performance target of these cards is somewhere around GeForce GTX 1060 level.