Asking to see the pager log can be quite revealing as well. I worked at an MSP where you could expect 1-5 pages per night while on-call. It was definitely hidden during the interview process and I bet they never would have been able to hire anyone if that information was revealed.
I was actually recently discouraged from applying to GitLab after seeing their public on-call weekly reliability newsletter[1]. I've been on-call in all of my positions, but the level of incidents they seem to go through in a week seems like it would be very stressful. This isn't to throw shade on GitLab though, I absolutely adore what they do and use it on a daily basis <3
