Yes, of course, but I think we are talking about seeing a Pilot episode IN RETROSPECT, having already gotten used to an actor being in the role and not feeling that anyone else could fill those shoes.
Personally, it would be too weird and I would prefer not to but I can certainly understand other peoples curiousity.
You are right, we would not be having this discussion if Robin Stewart had taken the role and he was the only Steve ( Paul) we had ever known.
I am just thankful that fate, or whatever else intervened at the time and we got Steve Hodson. I couldn't watch the pilot now, in retrospect, with another actor. But that's just little ol' eccentric me.