Well, the IRS def knows anyone who's moved over 20k through their coinbase account in any year since 2013.
I don't think it would be too difficult for them to expect anyone on that list to claim taxable income or at least list some crypto assets for 2017... They are likely more interested in the folk making big money. There has to be a cost/benefit analysis. "How much do they likely owe us / how much will it cost to audit"
Probably best to have multiple outs to fiat. But bitpay is tied to my social, as well. Will have to get extra creative in coming years if yer bent on dodging the tax man. Better bet is to earn enough to be able to afford a good tax advisor.
https://www.theverge.com/platform/amp/2017/11/29/16717416/us-coinbase-irs-records