Is there some reason this wasn't done 100 years ago? 50? 30?

Methane outgassing/flaring from oil extraction operations has been going on the entire time we've been oil drilling. Why didn't the oil companies extract this resource?

And who is c3es? Wikipedia says they are a rename from the Pew Center for Global Climate. It may be a logical fallacy to question the motives of an argument, but it isn't a policy fallacy to know the motives.