I'll refer to what David McLaughlin mentioned: “trust, but verify.” We should trust our officials, but it's important to have a conflict of interest regime and outside monitors to assist them. The Ethics Commissioner should be seen not as an opponent, but as someone who is helping and working with officials to establish trust.
I don't think a well-run conflict of interest regime should exclude people of wealth or people who have done well in business from entering politics. There's no evidence that it has happened in, for example, the United States—excluding the current regime, which doesn't observe any of the conflict of interest laws. Very wealthy people have found the privilege of serving in government worthy of putting their holdings in a blind trust for a while, and they haven't suffered financially as a result of that, or they have recused themselves and have held on to their wealth—they don't even have to get rid of it. If disclosure is the regime, they can hold on to their wealth, but it's just disclosed.
There's no real inherent opposition between conflict of interest law and people from the business community entering politics.