>And eventually the asset class becoming mature, so fees also fall by another 90%
Are we talking fees for coinbase pro, or the spot price offered by coinbase on their website? The prices for the former are already pretty low, with most exchanges charging around 0.2% on their lowest volume tier. The prices for the latter might be high, but I can totally imagine it staying high considering that forex rates at your local bank is equally as bad (around 1-2%). As a point of comparison for both, transferwise charges 0.4% for converting euro to usd.