If the Republicans called their bluff they'd either have some of the democratic senators "break ranks" to vote against it and/or Biden would veto it like how he said he'd veto Medicare For All. The Democratic party as a whole doesn't want to enact policy and they don't want a majority such that they have no excuses not to do so. They just want to fundraise...cause that's all this shit is. America is just grifts all the way down.