Android only requires GLES 2 yet 63.6% of devices support GLES 3+ anyway.
Since nearly everyone's GLES 3 hardware both supports vulkan & has vulkan drivers already there's no particular reason to believe that an OEM will decide to just not ship vulkan support. It's more work for them to remove Vulkan from the SoC's base image than it is to just not touch it.
The low-end GLES 2 hardware is the only problem, which is a market iOS simply doesn't exist in at all. So if you're cool with ignoring that market, go for it.
Since nearly everyone's GLES 3 hardware both supports vulkan & has vulkan drivers already there's no particular reason to believe that an OEM will decide to just not ship vulkan support. It's more work for them to remove Vulkan from the SoC's base image than it is to just not touch it.
The low-end GLES 2 hardware is the only problem, which is a market iOS simply doesn't exist in at all. So if you're cool with ignoring that market, go for it.