Absolutely worth research. It's also worth research (before action) to try drastic countermeasures that don't involve reverting the earth to an earlier state. For example, animal methane production in the US is not much higher than it ever was. If a "vegan revolution" happens, the animal methane production in the US will be dramatically lower than pre-civilized homeostasis. Probably not a big deal (since it's such a tiny percent of GHGs anyway).

Similarly, I agree we could find a way to reduce cow methane production that could be given to the actual countries (potentially) contributing to global warming with their livestock... And also similarly, we should take each step with some care so as not to worsen the situation.

We think we know a lot about carbon and global warming, and we do. But we need to remember as we look at this stuff that we don't know everything.