This is a very one-sided perspective on things. Any precomputed solution to lighting comes with enormous drawbacks across the board. The game needs to ship the precomputed data when storage is usually already tight. The iteration cycle for artists and level designers suchs when lighting is precomputed - they almost never see accurate graphics for their work while they are iterating because rebaking takes time away from their work. Game design become restricted to those limitations, too. Can't even think of having the player randomly rearranging big things in a level (e.g. building or tearing down a house) because the engine can't do it. Who knows what clever game mechanics are never thought of because of these types of limitations?

Fully dynamic interactive environments are liberating. Pursuing them in is the right thing to do.