Miners are the definition of unreliable clientele. Volatile (10s, 100s of thousands of orders one month, 0 the next), they flood markets when they are done with a card (unlike gamers and workstations, which retire their cards at vastly different rates), and of course, the stigma from even working with miners.
There is nothing to be gained from catering to miners, unless if your GPUs are good at mining and uncompetitive in the core gaming market. Right now, anything, even ancient Polaris, are flying off of the shelves. Everything is wildly competitive and in-demand in the gaming market. Overall, better to sell to traditional consumers than catering to mining.
Also, somewhat unrelated, but Nvidia was once, and was long the largest customer of TSMC, before being displaced by Bitmain (a mining ASIC company) a few years ago. I wonder how much of TSMC's production allocation is still going to mining. Same with UMC, SMIC, GloFo, any the myriad of other logic fabs out there. Well, probably not SMIC, given China's official policies on mining.