Once that's solved people will start using Bitcoin and then I doubt your statement.
BTC has 2 problems then. It can't compete with visa and mastercard for transaction speed. ASICs are the bane of decentralization. China wins the ASIC race due to power costs. Some alts will go to extreme power effeciency, which will limit centralization. Allowing hobby miners back in. That's a third problem for Bitcoin, it has had a few half assed updates in it's lifetime and there are alts that can adapt to any situation. Bitcoin probably won't stay number one, it's only a matter of when, not if.
Technically, many alts are genuinely superior to bitcoin. The problem is no-one knows about them outside the cryptocurrency space. The mainstream media and Wall Street are fixated on bitcoin (as are all those venture capitalists in Silicon Valley hoping to create applications on top of bitcoin).
Marketing alts is HARD.