Are you sure? Cows eat plants. The footprint from cows is largely due to the fact that you need 14 pounds of grain per pound of cow, if I remember correctly. Unless these burgers are somehow taking 14 pounds of grain to produce per pound of burger, I think we're in a better place.
That said, eliminating cows I still don't think will help the environment. That freed up land will be bought and used for some other purpose. It's natural capitalism. If you want to fix the environment, you need heavy penalities / taxes for nonsustainable resource usage. That's the only way.
Cows don't need grain. Grain feeding is part of industrial meat production that is highly detrimental to the environment. Feeding cows grass (and rotating them) though has the total opposite effect. It creates soil that can hold more water and sequester carbon. So it eliminates the need for grain production because cows simply eat grass while naturally fertilizing it.
That said, eliminating cows I still don't think will help the environment. That freed up land will be bought and used for some other purpose. It's natural capitalism. If you want to fix the environment, you need heavy penalities / taxes for nonsustainable resource usage. That's the only way.