Cryptocurrency Taxes Example - Double Whammy?

[Scott Trench]

I have a question about cryptocurrency and tax implications. 

Suppose I am paid $10,000 for a job or service I perform and receive the amount in Bitcoin. 

I understand that I need to treat the $10,000 in bitcoin as taxable income, and would owe, for example, $3,000 at a 30% income tax rate. 

However, what happens if the bitcoin drops to $5,000 in value shortly after receiving it? 

Does this mean that if I sell it all, I can claim a $5,000 loss? 

And one more question: 

Suppose I'm a really high income earner, like an NFL quarterback. I receive $10M in taxable income in the form of bitcoin in 2021 when bitcoin is worth $65,000. 

My tax bill comes due today, when bitcoin is at $21,000. 

In this instance, I'd owe 2021 taxes of perhaps $4.5M at a 45% effective income tax rate.

However, my bitcoin is only presently worth $3.2M. 

Am I SOL? Or, can I sell today and use the huge loss to offset my income tax liability from the prior year? 

@Daniel Hyman and @Nicholas Aiola I'd be particularly interested in your thoughts on this!