Seems highly unlikely. No one with millions of dollars to spend on a Bugatti is going to wait 3-4 years for their car to show up.
You can already find used/unsold ones too, so anyone in their right mind would just buy one currently available and have it repainted/upholstered.
Buying a Chiron with expected delivery in 2022 would be like buying a Veyron with expected deliver after no one wanted the coupe anymore and everyone moved to the Gran Sport.
And yet, it is the truth, Chiron is always extremely desired.
Look at the "110 Ans" edition, the 20 copies are sold directly.
There is also the example of Chiron Sport, since its announcement, more than half of the Chiron ordered since then are Chiron Sport.
The same applies to the "Sky View" option.
I could talk about the Divo, which instantly sold for €5m, but it doesn't directly concern the Chiron series.
And I guarantee you that it will be the same for the next one.
All this to say that Bugatti has no "problem" to sell.