Yes it would ablate at some rate, based on the drag, convective buoyancy, etc. If the smoke is optically thick at all, even if it pushed away almost immediately, the wall ablation rate would probably be a couple orders of magnitude lower than if the laser hit the wall directly...

If you want a fun read, the Galileo probe wall ablation paper is fun, the re-entry power density (at the wall!) was ~10kW/cm^2.