Is there any republican justification for this, other than, by the time people notice it will be too late / we will try to blame it on the other party? Are they expecting the states to step up and pay instead?
They're setting the ACA up to "naturally" fail anyway, so this doesn't matter to them, or is even a step in the right direction.
They kicked out one of its three "legs" (the "individual mandate") so this right-wing heritage foundation promoted healthcare scheme is now guaranteed to face a price death-spiral anyway, unless that changes.
They gave up on repealing it, because it was so popular, and have settled for breaking it in ways that most folks will have trouble figuring out they should blame Republicans for (those chickens won't come home to roost for years, and I guarantee it's only a tiny minority of voters who understood the necessity of the mandate for the whole thing to work, anyway), so eventually it'll be popular to get rid of it.
> by the time people notice it will be too late / we will try to blame it on the other party?
This is it.
A lot of the things that the Republicans are doing that will completely fuck the lower/middle class don't actually take effect until after the mid-terms. This is an insurance policy so that if they get absolutely wrecked in the mid-terms, they can point to Democrats having the majority push blame onto them. On the flip side, if Republicans maintain control after mid-terms, by the time the next election takes place, people will have forgotten who it was that screwed them over.
Alternatively, they can just keep saying it's all Obama/Biden's fault. That still works.
They're misinformed voters that will be told that their food is more expensive because of Bidenflation, not because ICE arrested and deported the farm workers. As health care gets more expensive, they just get told it's because of ObamaCare.
When in doubt, just cry "WOKE!" and "DEI!" and they'll bend over for Trump and any Republican that claims to be friends with him.