If bitcoin is worth anything, then most Alt-coins in the top 80/100 (except shitty Bitconnect) are worth more. Bitcoin only has the Name (=Fame), Numbers (=More users -> More stability). In a market where technology, ideas and teams don't actually make the worth (but only enable you to make a difference between a coin to another), a name and a big number of users takes a LOT of time to dethrone. But look at how quickly BTC is losing dominance... I think we'll see a 25% dominance (vs the actual 32/25%) by the end of 2018