The SCOTUS overturned the 'Constitutional right' to abortion. It is no longer a federal issue and states have reacted accordingly.
Taken literally, that's correct, but only because there was no federal law in place at the time of Dobbs. But there is nothing in Dobbs itself barring the federal government from passing a law on abortion.
I don't see where the commerce clause power has been expanded -- then again I'm not a lawyer. I'm relaying my understanding after reading many articles and the opinions.
The initial understanding of the commerce clause was that it only regulated the movement of goods between states. Over time, it was expanded to include any economic activity within a state that
impacted interstate commerce, which is a far broader definition.
The most infamous) commerce clause case that expanded that power is Wickard v. Filburn, which held that the federal government could regulate the growing of crops on a farmer's own land, even if he never sold any of it, based on the idea that because he was growing crops for feed, he wouldn't be purchasing them on the market, and him NOT purchasing feed would have an impact on interstate commerce. There have been recent attempts to reign in that decision, but the clause is still interpreted far too broadly.
https://www.nbcnews.com/politics/supreme-court/supreme-court-wipes-away-constitutional-guarantee-abortion-rights-over-rcna18718
If you reread that article, you will notice multiple references to passing federal legislation in response to Dobbs, and no claim that Dobbs itself would prohibit that.