The main issue is time commitment. I have spent 5-6 hours learning and coding an algo maze thing in ES6 for a lead Ruby dev job because they wanted to know how my JS was. ended doing a day of ingerviewing mainly about design, JS and React. I did well because even if I know backend best I know frontend a lot too. I finnaly didn't get the job because they wanted somone only frontend not backend... For a Ruby job.
Yeah, its a mixed bag. I could make the test harder, so there's more you have to code, but I'm afraid I'll then filter out the more desirable candidates who have more than one test to do.
I think the main issue - as a candidate - it's hard to make the difference between companies that are serious and not.
Like this one, only one person reviewed my code and he didn't know JS. I had re-prove that I know JS at each interview because my resume shows morw backends experience. I didn't care personally because I need very little to have fun and I have money plus some passive revenues. However, I can see why people are exhausted by this process.
