The people pushing this are probably releasing more gas into
the environment than cows are.
This was started by American marxist and con artist Jeremy Rifkin of the fake People’s Bicentennial Commission (PBC) in 1976 and the pro -Hanoi Citizens Committee of Inquiry into US War Crimes in Vietnam.
Rifkin later changed the old PBC into an extortion type racket (a prototype template for Black Lives Matter) known as the People’s Business Commission. He used the cow carts-methane argument to transform himself into an environmentalist leader.
There is a lot on him on the internet including Frank Watson’s and others testimony about July 1976 before the Sen. Internal Security Subcom., Sen Judiciary Committee and at WWW.keywiki.org.