“Anyone know why I XYZ isn’t working on staging?”
A day passes.
“XYZ isn’t working on production!!!!”
Pre-production environments are only useful if they replicate production as closely as possible.
If pre-production escalation isn’t the same as production escalation, that’s just another way that it’s different, and one more reason to scrap it.
The point of pre-production is to catch issues before they make it to prod. Without a near-identical environment, including escalation & incident policies, these environments will not be effective.
When there’s a staging issue that would impact customers, and justify an incident response were it on production, respond that way in staging too.
We try and catch problems early because the faster the feedback, the easier the fix and the lower the impact.
If you don’t treat a staging problem like it’s a prod problem, it will be a prod problem soon enough.