They said the same thing when sound was added to movies, or colour, and we will say the same thing in 40 years when you get proper holodecks like in Star Trek.
"3-D films have existed in some form since 1890, but were largely relegated to a niche in the motion picture industry because of the costly hardware and processes required to produce and display a 3-D film, and the lack of a standardized format for all segments of the entertainment business. Nonetheless, 3-D films were prominently featured in the 1950s and 1980s in American cinema"