The passphrase to one of my TrueCrypt volumes is around 30 characters long. It's not completely random, so let's say it only has 2 bits of entropy per character. That's 60 bits total. A brute-force attack would take an average of 2^59 guesses before it succeeds.
At 10 seconds per guess, we're looking at approximately 180 billion years to crack my passphrase. Even if you devoted a million computers to the job (as an extremely well-funded adversary might do), it would still take 180,000 years.
If you weakened the PBKDF to take 1 second instead, it would take 18,000 years to crack my relatively weak passphrase using a million computers. That's still long enough that I don't care at all. Moreover, if I were really paranoid, I can easily bring it back to the 180,000-year mark (or more) by adding a few more characters to my passphrase, which would only take another second to type. So why wait 10 seconds?
E.g. 20*10^9 ripe160 hashes per second on 8x AMD R9 290X (price is around $3000): https://hashcat.net/oclhashcat/
60 bits are not secure against attacker with medium budget.
The point is that there's no need for a PBKDF that takes 10 seconds on modern hardware.
Sure, that 60-bit passphrase is weak. But it takes a trivial amount of effort to increase the entropy of a passphrase. Let's say I increased it to 80 bits. In terms of brute-force resistance, that's equivalent to increasing the PBKDF's iteration count 1 million times.
Plenty of older people started using computer in the middle of the sixties. So what if we started with card punch machines, tape readers, and mainframes?
Just exactly what do you mean by "normal?" How much computer exposure does it take before one loses that quality and becomes, well, "you?"
There are lots of grandparents coding away in cubes across the world or tinkering with their prized home-brew desktop rig. Take a reality pill, kiddo.
If anything, there are fewer younger people who will tinker with crypto because the vast majority of them think they're invincible, indestructible, and immortal, when they're really just inexperienced and gullible.