I have tested MacBook Pro 16 inch on Big Sur 11.2 - only the release date is 2020 november (my laptop 2019 december) - and it has no Slow UI, input, cursor stuttering lags - . Apple must replace such notebooks - but instead - the authorized service center said that everything is fine all the tests pass

the cursor stuttering bug is still not fixed for MacBook 16 inch BIG SUR 11.2 - Apple doesn't seem to care about us - it hasn't been able to fix the bug since the macbook pro 16 inch was released