The times when it would be most useful, as far as I'm concerned, and the only times when you get anything "premium" is when you travel internationally. Since you're Plat already, that's already covered.
For me, it's not worth it. Except for flight delays and such, I don't spend too much time in the airports these days. And now that no one travels, the airports aren't as crowded, nor are traffic related delays as common.
As I've said a million times, I'm not joining unless the price goes down or the service goes up, a lot. I'd be willing to pay more for a truly premium product; that's not what AA is offering. The AC is like Holiday Inn Express.
d