We were talking about the constitutionality of a head tax, since the mandate structure is, at core, a poorly structured head tax.
No, it's not. It's only a "tax" on people who don't buy government approved insurance. Which violates the key justification for why a head tax is constitutional (ie it applies equally to all citizens).
*the word tax is in quotes here because Congress, and the president deliberately avoided calling it a tax - the President adamantly denied it. So at the very least, regardless of the equivalency, the law was passed on false claims, given that it would have enjoyed even less public support had it been understood widely to be a large tax increase.