The Short Version
Meta killed its waveguide glasses project over cost and battery limits, while existing smart glasses still lack prescription support for the 75% of adults who need it.
Waveguide smart glasses, the kind that project images directly into your field of view, look like the right long-term design but cannot ship at a price people will pay or with battery life that holds up through a normal day. Meta already killed its own waveguide project because of this. The glasses that do exist, like Meta's Ray-Ban frames, skip prescription support, which matters because roughly 75% of adults need vision correction and would have to wear contacts underneath or carry two separate pairs. Most potential buyers are not an edge case.