I have a mid 2015 MacBook Pro i7 quad core, 16g RAM, Dual graphics processor. I have issues in the Develop Module with LR 10.1 and Big Sur. Every other module in LR works fine. As an experiment, I downgraded LR to version 10 and everything worked fine and no issues. In the last week, I have updated back to LR 10.1 and the problems in Develop are back. It is worse when the image is enlarged. As I am typing this, I am downgrading back to version 10.0
Crash or freeze, Mac, Performance, Problem or error
Lots of reports here and in the official feedback forum of problems between LR 10.0 and 10.1 and Mac OS in general and Big Sur in particular. One of the identified causes is having a custom color display profile produced by a calibrator; some others have reported disabling the graphics processor helps. And some have found rolling back from 10.1 to 10.0 helps (as you're doing). It's a mess.
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