Buran was never intended as a replacement for Soyuz, I suppose. Buran + Energiya were more a replacement to Proton, and a Space Shuttle-like capability to build advanced weapons systems in space, which would require extensive human labor and maintenance.

The space crew for these systems were intended to be armed with laser pistols, with prototypes produced: https://www.popularmechanics.com/space/satellites/a21527129/...