I think you make some really good points. But I would add 1 caveat. I'm absolutely willing to lose a couple days for a job interview, if I have a decent chance

I think you make some really good points. But I would add 1 caveat. I'm absolutely willing to lose a couple days for a job interview, if I have a decent chance of getting that job. If a company is asking me to complete an 8 hour test and they have already received 100 qualified applications that have also completed that test, I should know how many people have successfully completed that test. Giving a free 1/2 week of work for a job you have a > 10% chance of getting is very different than being asked for that kind of work for a 1% chance.