Remind me of the last time corporations got a Constitutional amendment passed?
Have you met a lawmaker, or been involved in the passage of a law? The state of civics education in America is such that a minority of folks understand the first rule of politics: showing up is half the battle. Unfortunately, pitching nihilism is a good way to keep the other side from bothering.
Why do you assume I live in the USA? No, I haven't been part of any legislation process in the USA because I do not live there.
No need for Constitutional amendments when the healthcare and insurance industry in the USA (the biggest spenders in lobbying afaik) can lobby politicians to block legislation setting caps on drug prices paid by the government through ACA, or to keep the dysfunctional system of health insurance you live under.
Let me know when citizens can spend some US$ 8-10b on lobbying for universal healthcare, just like the combined spending of healthcare + insurance industries...
And just a quick edit: setting the NRA as an example of citizens' association lobbying is a bit tone deaf given what they do for the weapons industry, it's another very good case for how lobbying can be detrimental to society by hiding big corporations interests behind what is seemingly a citizens' association.
Edit as a form of last reply since I got rate limited:
You edited the comment to remove the sentence saying "state or federally" which implied to me you were talking about the USA. A bit of a dishonest response after such edit...
I have in America, a few European states and India. The people who benefit from restrictions on lobbying are those with personal access to power. Because the lobbyists let the little people and those faraway get the access they believe they earned, bought or were born into.
I forgot about the impotence of Greenpeace, the NRA, the ACLU and EFF, of Susan B. Anthony.