Would you take the night shift? Everyone I've seen promote this idea seems to expect that they'll be the lucky ones who get to keep a normal schedule. If you have a service that needs 24/7 uptime, and you transition from an oncall model to a shift model, at least 2 out of every 3 engineers on the team are going to have to change shifts or quit. If the entire industry shifts, high-availability software would simply join the ranks of fields like nursing or manufacturing where many people have no realistic option to work normal hours.

I'm the one who wants to do the night shifts. I miss the time when I worked with a 13-hour time difference due to time zones. But now I don't have the option of working at night, everyone has to be at work during 'business hours', and yet the company I now work for has an on-call policy, and they only pay a tiny bonus to people who join the initiative.

The sane way to solve that problem is to hire people in different time zones to get coverage. Some still need to do weekends but even those are not the same in every country (e.g. Israel).