The actual question is if Eaton overstepped his authority in this ruling.

Instead of ruling narrowly that named plaintiffs would get a refund

Eaton expressly said:

"all importers of record" which is all who were subject to the IEEPA duties.

It is unclear if this is lawful.

He didn't have to do this at all. He could stuck with tradition here. He specifies why he did it in this case, but this opens the door.

Also note that he did not open the door to "final liquidations" getting refunds (it is unclear how many tariffs more than 180 days ago were not officially protested).