Let me first start with the lobbyist part. This is part is mostly seen in systems where this is ingrained in political culture. The Netherlands for example has 1 time a year where lobbyists can go and talk to the political parties and representatives about their ideals. The rest of the year it can be seen as political fraud if handled in certain ways.

The USA Political system has a large portion of it ingrained in its economical standards. This means that it is not only ingrained but seen as normal by a lot of people, and certainly does who are in power or benefit from it. Lobbying is also part of our economical systems due to the influence on production these huge conglomerates have.

“Why haven’t we figured out a proper form of government”

I think the answer to that can be pretty short. People are and will always think different of things. If you benefit from something, then that system si great. If you do not benefit from it the system is terrible. There will always be a divide in race, class and wealth which influences our progression in political thinking