the other thing is that this is the first 1/24 AM kit from tamiya, and the first 1/24 AM kit from any maker for some time...i do recall some earlier DBs have been 1/24-ed by italeri or some sort
i thought the Tamiya 1/24 Enzo Ferrari did open doors...and so are Fujimi's Lambo Diablo
the other thing maybe the complexity of such and the sacrifice in realism doesn't work out well so they couldn't be bothered to do it with normal doors