Why didn’t they “just” build a five story Death Star interior for just one shot instead of “relying” on visual effects trickery?

“Star Wars” (1977)

@tvaziri to ruin my childhood? I don’t remember which Star Wars things wronged me anymore.
@tvaziri HEY, we know they *did* and you just comped a floor in the picture on the right.
@tvaziri damn, totally breaks the immersion. they should have done it practically like the orig… oh wait.
@tvaziri shiny floor = primitive Volume, hence filn bros won't like it