I’ve posted this before and there is never a response, so I tend to view cross chaining in the eye of the beholder.
The industry has never published any guidance on the maximum chain angle, off centerline, from chain to cog. Meaning, if the angle of the chain on a 1x11 is greater than a big-big or small-small of a 2x7, why is there excessive wear on one and not the other?
My rough calcs put these angles between 2* and 3*.
In a lot of ways cross chaining is little more than being a bit lazy to not shift to another chainring for a short duration. It is funny looking back 40 years when freewheels were 5 and 6 speed, some people would run a half-step setup and constantly shift both the chainrings and cogs to mitigate gaps in gearing. And 1x systems eliminate the FD entirely to get “similar” half-step gaps.
John