I have a lot of problems with this paragraph, the same problems I see again and again on both sides of interviews.
> "Difficult to work with" is perhaps too harsh a statement
That's exactly what the OP meant to say, and verbatim what they would have said in an interview debrief. The interviewee wanted some amount of compromise, and all of a sudden they're "difficult to work with". Now everyone else in the room is framing this potential hire as an asshole. There's no coming back from that. I've seen this happen many times. One term of phrase like that and instantly a qualified candidate is out because someone latched onto a single fault and made wild extrapolations about it.
> just a low-investment screen
You have no idea how much of an investment it is. I've had hacker rank problems that I was expected to spend 3 hours on. That's a pretty big investment just to get my foot in the door. Sometimes (read: often) the juice just isn't worth the squeeze. The employer wants me to give it my best when they're not even willing to come up with their own questions.
> uniform across all candidates
I see this a lot as the panacea of interviewing. Sounds good to have everyone on a level playing field. But if you start out with a crappy process, applying it to everyone equally isn't going to get you good talent. As an interviewee, I'll still be bitter about the bullshit you put me through, even if everyone else had to do it.