It just seems like a short sighted play. The general public's concern for healthcare has only been growing. Republicans already failed to repeal and replace the ACA once. If the court system were to overturn it without Congress being able to replace it (which seems likely), I do believe the consequences for Republicans would be a blood bath in the next election. I don't understand why they want to poke that bear.
On the contrary, I think Republicans might try to claim some deniability ("it wasn't us who killed it, and besides, it was unconstitutional!"), but either way, they'd be under a LOT of pressure to fill the gap.
If they tried to claim that they would be obviously lying.
Given that
1) Republicans have been openly and eagerly and loudly attempting to kill the ACA since before it was law.
2) It's Republican states that are suing to have it declared unconstitutional.
3) It's Republican blatantly-partisan judges who are agreeing.
4)
If it's declared unconstitutional, it's unconstitutional
because of Republican legislation (the TCJA setting the uninsured penalty to $0, which makes it "not a tax", which makes the requirement to have insurance "unconstitutional", which "forces" the Judicial branch to strike down the entire law because that requirement is unseverable from the rest of it (instead of, you know, just deciding that the TCJA setting the penalty to $0 was the "unconstitutional" part)).
It's such a ridiculous argument I can't even bear to see it floated here without calling it out. If the ACA goes down its 10000% on the Republicans, and every single American knows it whether they'd be happy with its demise or not.
If SCOTUS strikes down the ACA entirely, I find it hard to believe they wouldn't put a stay on the ruling for some period of time in order to allow Congress to come up with a replacement (or transition plan) of some sort.
The political trouble for the GOP is that an entitlement program like the ACA has immediate results, while a more market-driven cost reduction approach (which they would presumably champion) would take years to show gradual results.
And which market-driven cost reduction approach would that be? Remember, the ACA is mostly "market-driven", which is why the Republicans haven't been able to come up with anything better in the last decade. They hate it because of who implemented it, not because of policy details.