If Congress passes a law and SCOTUS strikes it down, are there any consequences for Congress other than the law not being enforceable?
No. There are no consequences for Congress.
This follows, in part, from the Speech or Debate Clause, which is a clause in the United States Constitution (Article I, Section 6, Clause 1). The clause states that members of both Houses of Congress:
shall in all Cases, except Treason, Felony, and Breach of the Peace, be privileged from Arrest during their attendance at the Session of their Respective Houses, and in going to and from the same; and for any Speech or Debate in either House, they shall not be questioned in any other Place.