It's just bloat that requires fonts to implement extra, useless symbols.
Citation needed. There's no requirement. In fact, most fonts have most of Unicode missing. It'd be insane to try to cover the entirety of Unicode with each new font released. The most complete font I've found is Arial Unicode MS, but even that has vast swaths of Unicode missing.
I think it's neat that there are so many obscure and interesting uses of Unicode. If you don't agree, well, just don't use it?
20 hours!? So why didn't you charge them? Sounds like they have good reason to ignore the costs if they get free help.
Just like a user won't start backing up files until they feel the pain of file loss...
Neutrinos are into physicists.