Precisely. The medium of value delivery is irrelevant, as soon as you extract value by borrowing against an asset you have completed a transaction and therefore is a point at which it could (/should though that's the debate I guess) be taxed.
In both cases (payment in bitcoin or borrowing against stock) your remaining position could go to zero leaving you liable for tax you don't have money to pay, but that's on you to manage better.
Realization isn't restricted to "unambiguous outcome with zero question to the providence or final outcome" even in the existing tax code, and what does "final" even mean.
It's mostly an administrative convenience that we work with sale as the archetypal realization event. And collateralized borrowing is a very good candidate for realization as it inherently involves valuation.
Regarding losses, yeah you could then realized losses which could be used to offset gains from other sources, rolled forward into future tax years and so forth. That's all a pretty normal part of wealth and tax planning for people with ample and complicated finances. They hire people to handle this, don't worry about them.
Capital gains are applied against a cost basis, in the case of your homeowner, their purchase price. Unless the house appreciates in value there is 0 capital gain, even if you made the mortgage a realization event and for some reason implemented this with no residence exemption or tax brackets. It's mad how this point has to be repeatedly explained through this thread.
I was talking about withholding, where I pay taxes that will never come due. On reflection maybe isn't a perfect analogy.
You haven't made a persuasive argument (or any argument really) against, you just keep insisting it's a bad idea.
One thing that stands out is you keep referring to "money that may never exist". That's not how tax works. You are taxed on the basis of your income, which is often but not always monetary. This is both intuitive and consistent with existing tax code. If you don't like it you have a much bigger problem than objecting to taxing unrealized cap gains.
You can absolutely elect how to be paid, you can earn income abroad, receive benefits in kind, stock compensation etc. ALL of which may still be taxed. If your tax return only relates to dollar items, lucky you
This is how... EVERYTHING works... Income tax brackets, 401k limits. I thought this was pretty obvious, from each according their ability and all.
They didn't set out their whole tax platform for their presidential bid friend. We can trivially blow down your straw man with a primary residence exemption or, you know, tax brackets.
Realization is the establishment of value not sale for cash (it just happens that the most convenient establishment of value for any non-fungible asset is sale). There are already some realization events that don't have associated cash flows, to do with overseas assets or certain financial instruments. Ordinary people don't need to worry about this stuff, it's not for them, and if you're rich you can trivially figure out the cash flow issue.
But capital gains avoiding tax for the life of a wealthy person who lives off collateral zed borrowing, then being stepped up in basis for their heirs is just embarrassing for the US.
This argument applies to my wages too if I elect not to be paid in USD. Are you arguing that, say, Bitcoin income should be untaxable just because it could depreciate relative to the USD tax liability it generates.
This is both a terrible strawman of advocates for this type of tax reform and a misrepresentation of what realization events are in the US tax code.
Sure "borrowing in assets does not make you wealthier" but it does provide an excellent basis for establishing increases in wealth that have already happened. Realization is a tool to avoid arguments and uncertainty around valuation, not a requirement that taxpayers have cash in a checking account to pay their liabilities. Posting collateral for borrowing inherently involves valuation so could very easily be made a realization event, it fits very neatly into existing law.
It may be a political impossibility but your dismissal doesn't suggest you've really thought about it.
Also "taxing everybody on income at the beginning of the year and then telling them tough luck if they get fired and never get that income". As someone in a high tax bracket (and state FML) who left the country mid tax year, bless you for thinking this doesn't happen.
My kid screams "un-let go" at me while balancing perfectly well. She understands, she does not accept.
Relevant case law: "While it is true that economic gain is not always taxable as income, it is settled that the realization of gain need not be in cash derived from the sale of an asset" https://supreme.justia.com/cases/federal/us/309/461/
It is in fact true, and clearly then doesn't mean that at all. We can and do control what constitutes a realization event, and borrowing is a pretty sensible candidate. I don't know why you're losing you mind over this fairly prosaic idea.