That portion is a basically a sunk cost. You don't have that money you're just holding onto it for the taxman. Assuming any future gains will be taxed at the sa

That portion is a basically a sunk cost. You don't have that money you're just holding onto it for the taxman. Assuming any future gains will be taxed at the same rate, in effect you are not earning anything more off of it by holding it as the proportion of tax will be the same. The only way it would be different is if you expect the tax law to change in the future in your favour.