4.7ohm resistor clouds/streams?

I’m wondering what is the job/purpose of the 4.7ohm resistor (R11) in the power section of Streams or Clouds? It acts like a fuse? Why that specific value or those specific modules? Warps and Braids has them too.

This resistor is part of a RC filter that prevents high frequency noise coming from the power supply to enter the regulator.

I see. And why only on some modules and not all?

All modules that have been marketed or redesigned after 2015 have it.