As has been said, if a car satisfies the scrutineers and matches all measurements and limits set in the regulations they’re not cheating. If they’ve found a loophole then the regulations are badly worded. The same thing happened to Brawn. Toyota, Williams and Brawn all identified a flaw in the wording of the regs that allowed for a double diffuser. Other teams missed it. Lots of teams were clamouring for a ban and disqualifications. Never happened as the cars were within the regulations. Same with McLaren’s dual brake pedals, F-Duct and Mercedes DAS.
The fia took a whole power unit away from ferrari.
The out come was supposed to be released in testing.
It has not.
"Brawn all identified a flaw in the wording of the regs that allowed for a double diffuser."
Wrong.
Brawn told the FIA about it(double diffuser\loop hole.) before designing it.
"The rear diffuser regulations are simply a section of the wider bodywork regulations, which also include sections which allow bodywork in areas not intended for the diffuser. More important is the fact that all three designs use a 'window' or hole to feed the top side of the diffuser. That hole is horizontal in the case of the Williams, vertical for the other two teams, and is located where the flat floor meets the diffuser. The Brawn and Williams cars have 'double deck' diffusers while the Toyota has a 'triple deck' version"
https://newatlas.com/formula-one-double-deck-diffuser/11260/