Yes cows are bad, or rather the way they are managed is bad. In North America, cows have replaced the millions of Bison that were roaming the continent. But the cattle are managed in a way that pollutes.
Cattle produce significant methane but don't hold a candle to termites. Termites produce
11% of the naturally occurring methane. That's one hell of an untapped energy source. I wonder what the comparison is, for environmental damage from burned and unburned methane?