Nor does it mean you got a disadvantage.
If AMD 'knocks it out of the park' then they will have an advantage. If their flagship GPU doesn't have any major driver/heat/power draw issues, and is 2+ times faster than the 6900 XT, they will gain market share.
Of course, I'm using 'if' here because we don't know yet. Most (all?) of the current rumors expect AMD's next flagship GPU to beat NVIDIA's next flagship GPU in pure rasterization power. There are also many rumors that expect a substantial increase in power draw from both AMD's and NVIDIA's next-gen GPUs. I think this will be troublesome for both camps as users who may have recently bought a good 700W PSU may find that it's already inadequate.
Anywho, we'll just have to wait and see how it unfolds.