Indeed. Backlogs can evaporate. Can you imagine anyone taking delivery of a newly built 737 in 10 years? 7 years? Theoretically, that's part of the backlog.
> Can you imagine anyone taking delivery of a newly built 737 in 10 years?
..yes? Companies are still placing orders, despite knowing how long the backlog is. I also expect the 737s will still be sold in 20+ years time, much less 7-10.
Why not taking delivery of a current plane in 7 years? What do you think the development, testing, certification and production scaling timeline is of a brand new airframe?
