The first point is the only real argument IMHO and as others here have said, it's prediction, not reasons. Here's the crux of the first argument:
1. At the same number of daily transactions, fees must increase 250 folds. Or,
2. At the same fee level, transaction count must increase 250 folds. Or,
3. Price increases 250 folds to $65000/BTC. Or,
4. A combination of all 3
#4 seemed like the question answered itself. Instead the author doesn't acknowledge #4 at all:
"However, neither one of these scenarios is likely to occur. Scenario 1 represents a per transaction fee of $10. Scenario 2 represents 290 transactions per second and close to 25 million transactions per day"
The second part of the first argument is comparing Bitcoin costs to credit card costs. What the author is trying to say is that Fiat->XBT, buy something, then XBT->Fiat is more expensive than credit card fees of 3%. But on Coinbase, for example, that would be ~2% in transaction fees and that will only go down as XBT inventory is held and pooled so not every purchase transaction results in a fiat conversion. That's only being done now as a bootstrapping strategy (and it seems to be working).
I think the author has some good points here but didn't seriously address them, only thinly speculated on them. I'm giving it an up-vote to hopefully have some deeper discussion especially around the first argument of Bitcoin's inherent costs.
A quick side note: I'd like to see an analysis of electricity costs of mining vs. mining fees. Mining fees eventually need to surpass electricity costs for mining to be sustainable after inflation-payments are gone. The difference between costs and fees is the margin the miners will make. To me, that would really answer the first argument.