Why is her not grabbing it even in the game. This is never an option anyone would want to use

Because holding down allows you to ignore the ledge, even when you can.
This is a global mechanic and also available at Smash, you don’t need to hold down all the time with Fleet in order to be angled down, as soon as Fleet does the second UpB hop, you can release the stick and Fleet should grab the ledge always.
I’m aware it’s a global mechanic. I’m saying it should be disabled for fleet’s down-angled up-b (and any other down-angleable recovery moves that put you into freefall, for that matter) because it is unintuitive and has zero gameplay applications.
I agree. This would be perfectly fine if ledges or something was in roa 1, since you could cancel the freefall into a walljump to get your upb back, but now we’re just missing ledge and SDing

I agree with this. It’s just a QoL change. There’s never a situation where you WOULDN’T want to grab ledge (except Kragg Pillar maybe…?) so this would be appreciated.