I could see a disadvantage of an over-enthusiastic FW numbering system in that people know the Axe-Fx Ultra's development haulted at FW 11.0, and going straight from 7 to 8 makes it seem like the Axe II's FW 11.0 is faster approaching, which people have kind of internalized as the Axe-Fx's maturity firmware number.
Of course, it's all arbitrary and the Axe-Fx II's "mature" firmware could end up being anything from 8.0 to, I don't know, FW 78.3. But still, it's something people might think about, and because of that, could hold off on buying an Axe-Fx II because hey, with the FW numbers getting so high, who knows, maybe there's an Axe-Fx III on the horizon somewhere we should hold out for.