Say if someone owns 10 Bitcoins which is not declared and government doesn't know about it (earned/mined etc but did not buy) and now that someone want to avoid paying tax on cashing it out. Can he simply move to countries where there is 0 tax like (UAE) specifically dubai and setup a company there and cash out crypto over years in dubai bank account and later decide to move to his home country with all that money. Since dubai has 0 personal tax and his home country can't charge tax on it because of non-resident of home country. Is this possible?
Capital gains tax only applies to bitcoin that you
buy not the ones you earn.
Most attempts to circumvent the system will be caught by the IRS and will get you punished severely. They have shown us that they will even jail celeberties if they try to avoid paying taxes.