It's about a 20x potential over the course of 100 years. The problem is, the sheer size of emissions from fossil fuels dwarfs any contribution cow methane gives to the atmosphere.
Like, methane in the atmosphere is really high right now, but it's not because of cows, it's because of fracking in Canada and the United States, which commits an order of magnitude or methane than cows ever could.
It would be like standing in a room with a raging inferno and pointing to a matchstick and say look, there's our problem.
Cow-warming has a bunch of problems that mean it's never going to contribute to being a significant factor in global warming.
It's self-correcting. Eventually methane is going to reach a certain point of equilibrium where the amount that's coming back into CO2 is equal to the amount being emitted and now you're going to be at a steady state again.
It's relatively small scale. Cows farting is not really that big of a deal in the grand scheme of things when we have factories producing millions of tons of carbon emissions.
It's easily fixed. There's lots of medications and other things you can do to cows to make them stop emitting methane, if it ever becomes one of our most significant problems it will be easily and quickly solved much like CFCs were.
Carbon emissions from fossil fuels have a bunch of traits that make it particularly nasty.
It's additive. Everything we admitted in 1960 is going to be around and heating the planet for 100 years yet
It was growing exponentially. Humanity has been emitting an absolutely mind-boggling amount of carbon. We've gone from what? 300 parts per million to 400? And the amount of carbon we're emitting every year now is higher than it's ever been, and every single year worth of emissions just adds on to the problem pile that's going to keep on getting worse for the next 100 years.
It's not easily undone. That carbon is never going to turn back into oil unless humanity goes out of our way to do it, and it's incredibly difficult to do. You would need the sum energy usage of humanity from the 1930s to today recreated and wasted on pulling the carbon back out of the atmosphere and sticking it in the ground.
Emissions from cows undo themselves in 20 years, entirely offset themselves through plant growth, and are easily massively reduced any change in our lifestyle in just a couple of years if we really wanted to as a society, with next to zero change in our lifestyle.
They aren't comparable problems and all you're doing by pointing at cows and acting like they're causing global warming is distracting from the real problem.