Actually, tax avoidance or evasion is against the law and regulation of any country. We are all aware. But is this the fault of anybody for not paying tax in Bitcoin? When Bitcoin itself is shortfall of Tax payment based on its characteristics in Blockchain. I do not for any reason takes this for a crime at all, when it is not that the Tax authority served me any Tax payment Demand Notice that I shunned. However, when the time ripe for that, we must follow and shall obey suit.
I would not say every country but generally, it is something that should be done in most places where it is very important and necessary. If the laws on it are strict, then anyone evading it will have themselves to blame. Some may consider not wanting to pay tax on their bitcoin, but I guess they would rather have to do a P2P transaction, and never convert to fiat.
If you are honest enough, you can even declare it in your annual personal income tax. And as quoted above, only cryptos that converted to fiat must be subjected to tax.
That is how I see it playing out in the long run anyway, and for those who would still prefer to leave whatever they have in cryptocurrency as it is, I do not see why I will have to pay tax on that. There is no point in the way OP putting it that I will be caught, as normal sense should make me realize that not paying tax in conversion to fiat is more like going against the tax laws since that may be considered as a capital gain tax.