I am not going make judgement on people's loyalty. If someone chooses to do 60 hours works more power to them. If people don't want to do side projects that is perfectly fine too. Seriously my motivation wasn't to suggest id penalize those without a side project. It was more from my observation that (from several l5-l7 candidates):

1. Despite the "let us work together" intent it is still an exam where you are penalized for taking too long or making a "wrong" assumption or missing a few bits,

2. Given above or not when confronted with a random question it can be easy to get very nervous unless you have built a similar system from 1 to 1b user scale or you have done tons of practise interviews with companies.

So apart from interviews being hard and what they are purely because of supply and demand I wanted to see if you can learn just as much from a more open book approach (with either a side project or candidate knowing the question ahead of time say the night before). It could even be more inclusive that way!