I think that people perceive being on call and having to work with messy legacy infrastructure as a restriction on their personal freedom and an anti-perk. We also don't compensate well for oncall shifts so that might be part of the reason that people see it as a lesser form of work and not as a special status that's only given to the best engineers. At other organizations it may be different... I hear FAANG companies compensate their on call shifts quite well (typically a percentage of base salary banded by SLA)