While I realize that coin-mining is the immediate and notable bogeyman, truth be told, GPU prices would have increased substantially anyways.
1) Total overall sales numbers for PCs are downward, although not among "enthusiasts" and "gamers". Translation, PC Gamers are a dying breed, except for those of us oldies and die-hards.
2) Because of that, neccessarily, prices would have to increase, to maintain R&D spending, to keep "neat-o tech" in the pipeline for gamers.
3) Mining purchases, although they are causing shortages at retailers, are actually GOOD, longer-term, as it means that the market for dGPUs is larger, mostly mitigating the loss of volume from #1, and slowing the rise of prices due to #2.
Note carefully, that we haven't really seen MSRPs increasing wildly, as we've seen retailer prices being gouged.
I didn't think much of the 3rd-party sellers gouging, as Newegg would release shipments at near-MSRP prices, but that's no longer true, as Newegg is 1st-party goughing now, with RX 580 @ $430+.
In theory, GPU makers and AIB companies, could shrink the "mining demand bubble", easily. Just produce MORE cards. Thus, the hashrate of teh network(s) goes up, the difficulty goes through the roof, and thus, profits plummet, and people want to get out of mining again, thus GPUs are cheap for gamers again.
By not meeting demand, these producers are actually maintaining the mining bubble. And why not? They're getting more for every GPU sold. (Well, if the producers started raising MSRPs, which I don't believe that they've done - yet.)