Off topic: Champions ruleset: A Disadvantage that isn't disadvantageous, isn't a disadvantage; it's a Quirk. "I can't see... but I can perceive the world around me as well as a sighted person" = Not Blind.
On topic: So the end result of 7 pages seems to be: "Leave logic out, this is MAGIC and this is D&D. Total cover = no targeting. Light/sight/keywords irrelevant. Certain specific spells, due to certain specific wording [even though this is D&D, and words are inconsistently used], negate this."
Having said that, I'm surprised no one said anything about magic missile. "You create three glowing darts of magical force. Each dart hits a creature of your choice that you can see within range." I've often thought this bypasses the wall of force. The missiles appear at the creature (not target) and hit them. No traveling of intervening space...