That is not the argument, nor is that a valid argument against the boycott, though there is linkage. It is simply wrong to offend as well as possibly endanger those with normal, Biblical moral sensibilities in order to accommodate the perverse disordered sensibilities of a minority. Free speech rights do not apply here. See arguments against the boycott responded to here, by God's grace.
And in any case, since Target wants everyone to "feel like they belong" but which means those who do not subscribe to this immoral inclusive policy do not feel like they belong, then why are you attacking the latter boycotting the store?
I think it’s a good argument that the boycott is vast hypocrisy.