Don't know how he could possibly calculate that bitcoin would be dead in 4 years if the change isn't made.
What he said was...."Transactions will get unreliable and it’ll get worse and worse over time. My fear is there’ll be no critical event that causes people to react—Bitcoin just kind of has a long slow death. I’m trying to set off alarm bells for ‘You know, guys, if we don’t do this, Bitcoin will be dead in four years.’ "My gut feeling is that he fears that there won't be a critical event
fast enough to save Bitcoin specifically. Gavin is perfectly aware that the Fiat Powers are like dogs with a bone on this technology, and it is taking almost 100% of their attention at present. ALL Financial Eyes are turning to Bitcoin Technology. Note that I say the TECHNOLOGY, as in the possibility exists that they say,
"lets just make a Fiat Coin using the technology and do it ourselves." The technology won't die. And if Bitcoin doesn't grow with it, they'll create their own Frankenstein Fiat Bitcoin.
Gavin is just being political, and not giving the Bitcoin the whole picture - because he knows it would be detrimental to the discussion if it came from him. Gavin honestly doesn't care if it is Core or XT - but he is afraid that Core won't get it's act together fast enough to stay the Fiat Powers from launching their own Fiat Coin/Blockchain. So he's pushing you. He just wants Bitcoin to be THE coin after its all over. Mike is a different story, with less pure motives in my opinion, but hey, he plays his part too.
And I think the 4 years is about right give or take. IF Bitcoin gets it's act together the entire transition to Bitcoin in the Global Financial world will probably take less than 18 months. IF they are forced to create their own Fiat Coin, then it will take a couple of years just to readjust / redevelop the Infrastructure towards a new coin, get it accepted, establish a wider user base, create a financial panic to FORCE people into it, and then..... probably after things settle in - decide bitcoin is now just an annoying Altcoin, and regulate it into the grave. So yeah, four years sounds about right if the Bitcoin Community continues to fall into an abyss of selfish bickering.
Here is something I just posted on the topic .......
https://bitcointalksearch.org/topic/big-banks-wallstreet-basically-proclaiming-war-against-bitcoin-1164717