Four-lorn
What is Dave wearing today? Dave is wearing a business casual polo shirt (blue) and pants (khaki). He is not sure the Stan Smiths count as business casual.
How does Dave feel today? Dave is in mourning.
What are the factors affecting Dave's mood? Dave misses his beloved, pre-Liquid Glass, macOS. He does not like his desktop, virtual or otherwise, to be covered with liquid or pieces of glass.
What else is bringing out the curmudgeon in Dave today? Dave isn't answering that. Dave is ordering you to get off his lawn.