Nope. That is *your* claim and argument. Bitcoin is a currency and a storage of wealth, while ethereum is a "fuel" for running decentralized applications, which they clearly also state on their web-pages. Thus, Bitcoin and Ethereum can *not* be directly compared, because they are not the same. But this all brings us back to how "perception" works in a observer's mind, does it not?
That's irrelevant. Both BTC and etherium are divisible by 8 decimal points. If demand is higher than supply, then of course prices will rise, but in neither case your are running out of the money/fuel. as they are divisible by eight decimal points.
Whether early buyers make money, that is totally dependent on the adoption/popularity/demand and supply rate, and that has nothing to do with your argument about running out of etherium as "fuel". That's silly.