True, 2X is insufficient. As is 8X. But they are steps in the right direction. The only direction that will get us to our goal. Larger blocks are a requirement for Bitcoin to be meaningful to humanity as a whole.
"The payment network Visa achieved 47,000
peak transactions per second (tps) on its network during the 2013 holidays, and currently averages hundreds of millions per day. Currently, Bitcoin supports less than 7 transactions per second with a 1 megabyte block limit. If we use an average of 300 bytes per bitcoin transaction and assumed unlimited block sizes, an equivalent capacity to
peak Visa transaction volume of 47,000/tps would be nearly 8 gigabytes per Bitcoin block, every ten minutes on
average. Continuously, that would be over 400 terabytes of data per year."
Over the long term, not a problem. How big was your disk a decade ago?
Note also that this is peak. We can tolerate transaction backlog, as long as it clears without too much time passing. Average is much lower. Note that the published paper makes a
fundamental logic error. Using a peak figure as an input to an average calculation is either gross stupidity or simple fearmongering.
Now lets actually discuss how we get Bitcoin into the hands of each and every person. What's your solution for that? Hmm?
What I'm trying to say is that we can't solve the throughput problem
in the long term by simply increasing block size. It will let us breathe for a while and then choke us again. Other, smarter methods should be employed for solving this problem. One proposal is the Lightning Network. There will be better ones to come, and we should embrace them.
I've been around the incessant march of technology long enough to know the it will indeed solve the issue in the long term. There may be some points where demand outstrips technical limits. But now is not such a time, and neither is the long term. LN may be am important component of the ultimate solution set. But it is in no way sufficient. There is no technology proposed that eliminates this fundamental bottleneck. Block size needs to be increased. Period.
Regarding your 30-year calculation, it is indeed correct, and is an interesting result. SegWit gets this reduced to 15 years.
No. It absolutely does not. You are not yet processing what I wrote. For a person who does not yet have Bitcoin, at least two on-chain transactions are required. One to get Bitcoin into his possession, and another to make his
one and only lifetime channel funding (how likely is this limit?). Now, it is possible -- however implausible -- that the initial purchase of Bitcoin might be combined with others in a single transaction that can take advantage of Segwit. However, it is
impossible for his channel funding transaction to be reduced in block consumption via segwit. The smallest it can be is one input and one output. So that latter set of transactions (the channel fundings) is a minimum of 30 years at 1MB.
Plus whatever it takes to get the Bitcoin into peoples hands to begin with (another 30 years in the natural transaction/person case).