I don't see it this way.  I see it as adding certainty.  I saw my accountant long ago and discussed Bitcoin at length, and our assumptions based on existing law were pretty much exactly in line with this IRS guidance.  And I am someone who has used Bitcoin in every role imaginable: I've mined it, bought it, had capital gains and losses on it, paid bills with it, accepted payment with it, embedded it in a product for sale i.e. "cost of goods sold", held it as inventory, etc.

Now with this guidance, the way I understand it, the risk of running a mining operation is now less, as if you have losses in a mining operation, deducting them should be pretty straightforward.  And just about every mining operation is going to start out with a big probability of incurring losses.  Beforehand, one would be inclined to worry that an auditor or examiner would have to be persuaded that mining was even a legitimate business endeavor that could result in a deductible loss in the first place (as opposed to a hobby where losses are not deductible because you're paying for your own enjoyment).

Based on my limited understanding, Bitcoin is being treated better than silver and gold under the law.