Would a grid-based view for collections ever be considered over the current vertical list? I’m on an ultrawide monitor and for me especially it feels like the vertical list isn’t using the space available, especially now that I have a fair number of games.

In your profile theme editor, you can switch your collections layout from list to grid. Is that what you're referring to?

Nah, I mean on the desktop app, when viewing your library Though a display like what the collections page offers would be nice