It discriminates against those who don't have an entire day to blast away on a single company, which will be a lot of people, and many will be older and have families.

It's one hour and then, three hours, which is probably just an estimate of time it will take to complete the assignment(s).

If you can't sit on front of a computer on, like, a Sunday for a few hours and complete the tasks, then how do you expect to actually work for the company?

Finally, this couldn't be a simpler process. You only have to actually sit through an interview for 30 minutes. Lots of jobs require multiple interviews with recruiters, management, and coworkers. This can be done at your leisure.

How else do you suspect someone should gauge qualifications for a candidate in a tech role? (Don't answer, please. The question is rhetorical.)

The only reason I would say to skip this is the pay, but I don't know OP's situation and $30k might be a lot where they live.