It is not something that will happen overnight.
The decline in bitcoin's market share,though,is pretty much linear(albeit choppy)
source:
coinmarketcapNow down to 80% share, Bitcoin's demise is almost a certainty:
(1) BTC is controlled by a cartel of probably < 10 Chinese businessmen (mining, ASIIs)...
The Chinese government could take out Bitcoin in 24 hours and no one would care...
The way the Hong Kong authorities allowed Bitfinex to swindle it's Customers tells you a lot.
(2) The 2016 block time standard is Graphene's 3 seconds (BTS, STEEM, others)...
This is very close to "real-time" processing required to do anything interesting on the web...
Frankly, I totally dread firing up Bitcoin and dealing with 10 minute blocks and $2.00 fees
(3) BTC is worth less than it was 3 years ago, that's a pathetic fact...
In tech, once something stops growing exponentially it's pretty much game over.
(4) Bitcoin has failed to go mainstream and is not even "hip" anymore.
(5) Bitcoin's organized culture of hate/greed which was totally exposed during ETH's recent troubles...
Is clearly holding back the advance of crypto in general (even more than the herd of scam artists here).
The crypto space is very dynamic and there will be big surprises in the next 2 years...
The opinions and polls here always support the status quo and have been dead wrong year after year.