[nullc]

That's a distraction. Were that the issue politicians and the media were actually concerned about they could implement policy which made it ineffective at avoiding taxes-- e.g. requiring appreciated assets used as collateral to throw off an implied return which you're taxed on and which gets added to the asset's cost basis. We already have analogous tax rules e.g. using options trades to nullify the risk on an asset causes it to be treated as sold for tax purposes.

The reality is that the total financial effect of that sort of technique is not that considerable, but the political noise that can be made out of turning it into a perpetual problem (e.g. by only proposing to fix it with drastic non-solutions like wealth taxes) is gold to the people that profit from making us hate each other.