The GMA T.50 sort of undercuts that argument a little, as it uses a largely similar engine, with a similarly lightweight body, and by all accounts is extremely reliable.
It’s true the aero is less complex, but I don’t think it’s the aero that makes Valkyries fail in such numbers.
Over at the SSO Report website they’ve documented the Valkyrie’s journey over the years. Aston got to a point where they lost money on each one delivered, so they tried to minimise costs throughout the manufacturing run by simplifying after the fact, and squeezing their subcontractor Multimatic.
That and fraudulently not paying the contracted profit share to their partners in the project (the reason all mid-engine Astons are currently on hold).
You can see why Newey launched a second attempt to make his dream car, but this time in house at Red Bull.