From a legal standpoint, yes it is constitutional as an undeniable fact because the court has said so.
From a standpoint of one's personal opinion such may not necessarily be considered as such simply because of this ruling. One can disagree with a court's ruling or find it to be incorrect and seek to delegitimize the court, or engage in a long term plan to change the composition of the court and hope for a reversal of what is considered to be a previous mistake.
An example of the first situation is exactly what the left did with regards to Citizen's United. The second situation is exemplified by the right's actions against Roe V. Wade.
The right has been trying to overturn Roe v. Wade for 30 years. How long will it take to get rid of the ACA at that rate?
The ACA has a better chance of being repealed by Congress. Roe could be in place forever or be struck down in a few years. There is never any kind of guarrantee of success with such a strategy. It took almost 60 years to overturn Plessy with a subsequent, "we fed up before" type rulling.
