DRAM is basically a crutch made to mitigate poor controller speed.
That's your point of view.
I do not want to loose my expensive GiB DDR5 RAM. RAM is very, very, very, very expensive.
The better technology is when a graphic card or data storage do not reduce my expensive RAM.
In my point of view - there is even more traffic over the PCIE bus because DRAM is missing for "caluclations" on the data storage.
I want to explain it with my current hardware.
The Ryzen 7600X processor talk via 4 lanes PCIE 4.0 bus to the first mainboard chip and than over the same bus speed connection with the next mainbaord chip. All traffic has to go through two mainboard chips and slows down the PCIE 4.0 4 lanes connection
there is less traffic with proper drives with DRAM.
There are still computers out there with budget dram less nvme wiht only 4GiB or 8GiB DRAM. Most likely often also with a graphic cards which steals DRAM.
I still have no idea how my backup media in the usb nvme bridge (ICYBOX IB-1817M-C31 USB Gehäuse 10Gbit/s USB 3.1 gen 2) handles the Western Digital sn570 1TB. That drive also does not have DRAM.
I wonder if there is some sort of fallback mode if that host buffer memory feature does not work.
