I'll agree that having an election not meet expectations is a reason that support for Trump might diminish slightly going forward because there are people who look at the result of the election and blame Trump after the fact. But it's not the other way around. In other words, the failure to meet expectations is the cause and the diminish in Trump power is the result.
Daily Presidential Tracking Poll
The Poll shows approval for Trump leading up to the mid-term elections. Support for Trump increased. At worst, you can argue that approval of Trump held. You can't really say that approval for Trump went down prior to the mid-term elections.
The decision by SCOTUS was inevitable. Ruth Bader Ginsburg herself pointed out the problem with Roe vs Wade. The case leading to the overturn of Roe vs Wade (Dobbs v. Jackson Women's Health Organization) came to the Supreme Court when it came to the Supreme Court (in 2022). Moreover, the impact of that decision in the public eye likely had far more to do with the leak of the decision months prior than it had to do with the actual decision itself.