In the country I live the 401k equivalent is taxed yearly on gains (and again as income when I retire), and I think that is fine - I get a world class society in return (you guessed right, it is a Nordic country)
so the answer is yes.
However, i did not go as far as proposing anything. You are assigning value on my statement.
I merely pointed out that it is a mute point to say that you can not use your unrealized gains.