Information on Rancher's Rate Limiting

I’d be happy, if someone could provide me with resources for further information on this topic.
There are so many open questions.

How can I access those configuration files in a Docker launched Rancher?
Is the rate limiting enabled by default? If yes, what are the default values?
Is there a way to configure rate limiting without using plain files? Is there something in the Rancher UI I can use instead?
Is there a difference between RKE and k3s regarding rate limiting?

I am facing the following issue and want to first exclude, that Rancher does some magic additional rate limiting, before the one from Kubernetes applies: