I like the idea of getting paid $500 or even $1k for a take home test. It's frankly a simple matter of respect. For employers, they're just asking you to do one task, but for employees, talking to 4-6 companies in an interview cycle can easily be 40 hours of interviewing and another 40 hours of work on top of that.

I'm at a point in my career where I mostly refuse take home tests because I'm busy and I value my free time. Getting paid would make me much more willing to jump through hoops. Particularly when that day of vacation cost me $350 after taxes, so it's not like I don't have skin in the game already.