Did this AirPods 5 report turn out to be true?

Right. It turned out the way this report said.

Who reported it first?

Mark Gurman reported it on Mar 17, 2024 in MacRumors.

That was 176 days before AirPods 5 was announced on Sep 9, 2024.

Mar 17, 2024BF5E-0004Right

Both fourth-generation AirPods models were expected to provide a better fit.

Mark Gurman reported that both fourth-generation AirPods models were designed to provide a better fit than earlier AirPods.

What was reportedBoth fourth-generation AirPods models were expected to provide a better fit.
Who said it, and whenMark Gurman reported it on Mar 17, 2024 in MacRumors.
What happened, and whenAirPods 5 was announced on Sep 9, 2024, 176 days after this report.
The verdict, and whyRightIt turned out the way this report said.No reason has been written for this verdict.

What do these words mean?

Right: It turned out the way this report said.
Partly right: Some of this was right and some of it was not.
Wrong: It did not turn out this way.
Moving target: This was right about the plan at the time. The company then changed it.
Never settled: The company has announced the product and nobody ever confirmed or denied this.
Not comparable: This measured a different thing from the number the company published, so the two cannot be compared.
No outcome yet: Nothing has happened yet that would prove this right or wrong.
Not checked yet: The company has answered this. We have not finished checking this one.
Checked: Checked means the company has since given an answer and we compared it with what was reported. Details still waiting on an answer, details nothing can settle, details where the plan itself changed, and details we have not finished reviewing are all counted separately and are not part of that number.
Moving target: A moving target is a report that described the plan accurately at the time, on a product the company then changed. We count these on their own: it would flatter a reporter to call them right, and it would blame a reporter for a decision that was not theirs to call them wrong.