No, tx/block certainly NEVER stopped increasing: https://blockchain.info/charts/n-transactions?showDataPoints...
And price is cyclical. After the bubble of June 2011, it took 21 months to surpass its previous high of $30. What makes you think this bubble and price correction is different? In fact, Bitcoin is on the rise since its $150 bottom on January 14th so it would indicate the drop in fact did stop.
> Dell does not accept bitcoin
This is irrelevant to the point the OP was making: transactions that remain within Bitcoin incur no fiat exchange fees. I sell something on craigslist for bitcoins, I use these bitcoins to pay back lunch money to my coworker, he gifts the bitcoins to his brother, his brother sends the bitcoin to his son overseas for remittance, etc. All this with zero fiat exchanges.
> But customers unfortunately are not
Growth is not through-the-roof, but it certainly is there: http://avc.com/2014/10/bitcoin-adoption-metrics/ You cannot quote 2 anecdotes and infer an industry-wide trend. The plural of anecdotes is not data. Anyway it's again irrelevant to the point the OP was making: the blog post's argument is flawed, not everybody who uses Bitcoin is doing it for illegal purposes.