People responding to this the way they are is not a sudden urging of their own, but because they are responding to a sudden full-court press of bluster and urgency in the social sphere. People were talking about lightning or RGB, or sidechains in general for a long time too, and the Bitcoin community has either welcomed or tolerated those innovations. Because a group wants something urgently to happen and believes "other chains will outcompete it on some specific factor" to the degree that "Bitcoin will be dead" and it "might be the only upgrade we ever need" doesn't mean it's going to happen without challenge. You're watching the debate play out. One debate like this a cycle ago with extremely similar urgency and rhetoric didn't go well for it's proponents.