Every federal agency (and I worked for one for over 30 years before retiring) "invokes" the "interstate commerce clause" in order claim jurisdiction of any regulated "product" that crosses state lines (or borders).
When "interstate banking" was pretty much expanded - H.R.3841 - Riegle-Neal Interstate Banking and Branching Efficiency Act of 1994 (and its amendments), that confirmed that banks could domicile in one state and open branches outside the state, and have their terms and conditions apply to their branches nationwide (including credit card interest rates).
I posted here about this conundrum, specifically with the card rates, that goes back even earlier - https://www.democraticunderground.com/?com=view_post&forum=1014&pid=3596130
The unanimous SCOTUS ruling that established this -
Marquette Nat. Bank v. First of Omaha Svc. Corp., 439 U.S. 299 (1978)
(snip)
MR. JUSTICE BRENNAN delivered the opinion of the Court.
The question for decision is whether the National Bank Act, Rev.Stat. § 5197, as amended, 12 U.S. C § 5, [Footnote 1] authorizes a national bank based in one State to charge its out-of-state credit-card customers an interest rate on unpaid balances allowed by its home State, when that rate is greater than that permitted by the State of the bank's nonresident customers. The Minnesota Supreme Court held that the bank is allowed by § 85 to charge the higher rate. 262 N.W.2d 358 (1977). We affirm.
(snip)
I would think, as you noted, that Congress would need to amend the various banking laws to deal with the rates versus an "Executive Order" unilaterally proclaiming a cap (and many of us have wanted some kind of cap for forever)!
An "Executive Order" is SUPPOSED to be a "guidance document" that informs the relevant Executive Branch agencies on
how to carry out existing laws (most commonly, through creating regulations, etc), NOT make up new laws.
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