Some boards have x1 slots below the x16 slot.Most GPUs are 2.5+ slots nowadays. Aren't these x1 slots mostly wasted?

Is this QVL filter broken?The left image shows there are more than 2 G.Skill entries, but after filtering on Q.Skill it returns only 2?  

What exact audio and network chips / controllers does this board (and other boards) use. It's not listed in the specs is it? https://www.asus.com/motherboards-components/motherboards/csm/prime-b650-plus-wifi-csm/techspec/

Only a few AM5 boards appear to have SPDIF out. Some very cheap ones have it, but no TUF ones seem to have it.Does Asus not believe in SPDIF? Is it decided at random?

Where do I find the feature matrix table for AM5 boards so I can easily compara them?