There is absolutely no difference between what you and I said. The Post Office does limit the priority of a business delivery unless that business pays a premium (express delivery).
The reason this doesn't goes terribly is that there is business competition between the Post Office and FedEx, DHL, etc.
The problem with the internet is not the lack of neutrality, it's the lack of competition between ISP.
And you assume that small businesses will be kept out. I see the exact opposite happening in Europe where net neutrality is more lax. Small startups are making agreements with ISPs to provide services that need a level of QoS that wouldn't be possible with net neutrality in place.
You are right that the problem is a lack of competition.
The biggest problem with internet companies right now is that there are services like Facebook that people use so prolifically that they are very difficult to compete with. If ISPs began prioritizing Facebook, as they have tried to do before, it will be even more difficult to compete.
The other problem is that ISPs aren't the only ones fighting competition between internet services. There is a long history with media corporations using copyright to fight competition. Most innovative music streaming services have been considered illegal (turntable.fm, Grooveshark, What.CD), unless their business can pay rightsholders (Spotify, ). and adding features to existing services like Netflix involves breaking DRM, which is also illegal.
All of these issues are related in some way, especially since many of the biggest media corporations are the same businesses as the biggest ISPs. These corporations have accrued so much capital that no one can compete with them or their lobbying.
The reason this doesn't goes terribly is that there is business competition between the Post Office and FedEx, DHL, etc.
The problem with the internet is not the lack of neutrality, it's the lack of competition between ISP.
And you assume that small businesses will be kept out. I see the exact opposite happening in Europe where net neutrality is more lax. Small startups are making agreements with ISPs to provide services that need a level of QoS that wouldn't be possible with net neutrality in place.