I wouldn't say it's without pay. It's in the job description when you're hired and the pay should compensate for that. SREs are typically paid very well.

Oncall being in the job description just doesn’t rationalize the abuse and insanity Ive seen myself and my team go through.

I don’t think a bullet in a job description and expected baseline pay for a tech job is reasonable enough to accept that either.

On call rotations are part of basically every engineering team that owns any production service at tech companies, not just SRE