The use of the CMYK profile for your own inkjet printing is also recommended. write J. Gulbins, U. Steinmüller.
What edition of FAP do you read? Mine (5th edition from 2018) does not recommend CMYK any more, just mentions it.
The other contributors have already explained the reasons for using RGB very well, just let me add some additional cents:
No matter what kind of data you send to an Epson print driver, it only understands RGB "as an input format". If you'd send a CMYK file to it (by printing ot from PS, i.e.), this CMYK data gets first converted to RGB, then into single dots of C, M, Y, K, VM, VLM, LC, LK, LLK... which finally become printed. At this point, the driver behaves like a RIP, it "rasters the image".
A RIPs (like the above mentioned EFI Fiery) does more or less the same, but without using the printer driver. It has it's own way to "talk to the machine".
Thus, to some RIPs you can send CMYK WITHOUT being converted to RGB first, as they understand this language.
Of course a RIP finally does the same as a printer driver: It "processes the raster of the image" into C, M, Y, K, VM, VLM, LC, LK, LLK...
Now, as print driver and RIP do more or less the same, what would be a benefit of using CMYK then?
The answer has to do with the profiles used for conversion. When building CMYK profiles, additional parameters can be defined, for example the way black (K) and dark colours get ripped (UCR, Under Color Removal; GCR, Grey Component Removal. In german this topic is called "Unbuntaufbau").
In the early days of inkjet printing RIPs were far more used than today, that's what I think Uwe and Jürgen refer to CMYK in their book. Besides, GCR/UCR can be useful when it comes to ink saving and proofing, as Andrew mentioned.
But nowadays, it's totally fine to forget about CMYK workflows, fortunately ;-)
PS: PM me for explanation in german.