All DRAM is fundamentally the same, which is why DRAM manufacturers can shift production between any DRAM products and even NAND on relatively short order depending on whichever has the better sales outlook for the foreseeable future. If DRAM manufacturers are shifting production from DDR4 to GDDR6 in anticipation of next-gen consoles and new GPUs sales, then there is less DDR4 to go around and prices on that will go up too. Very convenient timing for DRAM manufacturers looking for excuses to reduce DDR4 output and drive prices up.