repl-backlog-size 1mb is too small in most cases, but at the same time I think the real fix would be to make it dynamic (rough example: set min and max instead, and let redis choose a value in this range over time)

So let's collect suggestions of new defaults here?

Going to copy @xuliang0317 comment here to close the other issue.

Now repl-backlog-size is still 1mb,For most scenarios, this value is too small.Network transmission and bandwidth performance have improved rapidly in more than ten years，Memory is getting cheaper and cheaper.
Although the impact is noted in the documentation, most Redis users will directly use the default configuration.In many scenarios, the traffic per second of a single node exceeds 1mb.Especially for businesses facing individual users.
I recommend at least updating the configuration to 10mb to improve the rationality of the current repl-backlog-size.