Proposed Constitutional Amendments on Free Speech

I always thought of the First Amendment as pretty clear on the matter of free speech (accepting that there are limits) But Eugene Volokh questions a proposed Constitutional Amendment and wonders if anti-business non-profits (like maybe unions) would be exempt: Here is the proposed Amendment sponsored by Senator Bernie Sanders (I-VT) and a group of Democratic representatives:

Section 1. The rights protected by the Constitution of the United States are the rights of natural persons and do not extend to for-profit corporations, limited liability companies, or other private entities established for business purposes or to promote business interests under the laws of any state, the United States, or any foreign state.

Section 2. Such corporate and other private entities established under law are subject to regulation by the people through the legislative process so long as such regulations are consistent with the powers of Congress and the States and do not limit the freedom of the press.

Section 3. Such corporate and other private entities shall be prohibited from making contributions or expenditures in any election of any candidate for public office or the vote upon any ballot measure submitted to the people.

Section 4. Congress and the States shall have the power to regulate and set limits on all election contributions and expenditures, including a candidate’s own spending, and to authorize the establishment of political committees to receive, spend, and publicly disclose the sources of those contributions and expenditures.

Volokh talks about the rights of business oriented non-profits (read trade associations, chambers of commerce, etc.) which would seem to be barred from free speech rights, but anti-business non-profits (read unions and "public" interest groups) would not. Maybe.

But read that first sentence of Section 1. It goes beyond just the First Amendment, it speaks to all rights protected by the Constitution as the "rights of natural persons" AND do not extend. But what about the rights of the states? The 10th Amendment guarantees some rights (those not reserved to the people) although they are ill-defined. Would this Amendment alter that relationship? Reading the plain language, it would seem that way. Of course, a state is not organized for business purposes as we traditionally think of business, but many states are engaged in business which is not prohibited. Would those states no longer have an ability to speak on issues?

What about unincorporated associations? What about partnerships?

I don't think this proposed amendment will come anywhere close to ratification--but you can't help but wonder--why do people hate business so much?