In my opinion (everyone is entitled to his without solicitation, and that's acceptable as long as the opinion is not complete junk)...
1. The reason why people are buying Dash and Ethereum is not because Dash and Ethereum are better than Bitcoin, but because their prices are rallying. If the prices are not rallying, who would care if Dash and Ethereum are better (no, they are not). To say that Dash and Ethereum are better because of so and so is just finding justifications for buying into them.
2. The destiny/future/outcome of Bitcoin depends very much on the Powers That Be, specifically what the VC that invests $75 mil in Blockstream, wants for Bitcoin. Function as currency? Function as payment layer? I believe even if Bitcoin ultimately functions as just a payment layer, its investment prospect remain extremely large. Considering the fact that Core developers said transaction fee of $100 can be possible, this statement we can put into perspective on what the future value of Bitcoin could be. If transaction fee is fixed at 20,000 satoshis and this is equivalent to $100 (or maybe $50), then what may be the price of 1 Bitcoin in the future? $500,000 (or $250,000 for $50 fee)? This could be possible simply because if the price of Bitcoin does not follow the transaction fee, then NOBODY would use Bitcoin and the transaction fee of $100 would not even materialize. For it to materialize the price of Bitcoin will need to be at astronomical level for the whole thing to be commercially viable.
$100 fee? quite dubious. who would pay $100 when there's so much competition that is orders of magnitude cheaper?