Keep to the racing line and no one can pass you in Monaco, not real racing at all, no chance of a pass.
100% this. I watched that video waiting for some racing to break out, and it never did and never had a chance to do so. Senna blocked, Mansell had no chance of getting by without an error from the other driver. For me, this is the problem with F1. Mansell knew he could do nothing to get through, there was never a chance for him to do so.
I don't think the design of the cars in the early 90's helped either. They were a hell of a lot wider then than they appear to be now. Those cars would take up half the track in Monaco.