Responses
Not unless they're still financially dependent minors and/or living together under the same roof. But these two guys are both already financially independent, working adults, who are legally entitled to live apart from their parents (which also enables them to "not recognize" the new step parent as family if they don't wish to, as it's harder both for the law and for people to find ways to force an independent, grown up adult to accept a new *adult* family member).
Smh not step bros.. welp this is gonna be incest