Not sure about that. If the status quo were satisfactory, it's less likely there would be a vote to change it. That's a counterbalancing impetus to vote away from the status quo. Hard to quantify which way that would fall.
Furthermore, outlawing lobbying would encourage the contrary behaviour for candidates to keep their seats: the representatives visiting their constituents to hear their views. Lobbyists can voice their opinion at these town hall meetings, and I think it's clear that this makes it much harder to game the votes away from constituent interests.
The significant expansion of meetings to cover to stack the deck makes lobbying considerably more expensive, and probably not worth it unless it's a seriously important issue that would make or break a market.
I suspect that there would be a strong status quo bias in ignorant votes, so 50/50 is not a realistic assumption in my opinion. Not that this is even a realistic starting point to begin with because interested parties will alway try to disseminate information to law makers (directly, or indirectly).