Going under 9.9 is at LEAST as impressive as going under 10 used to be. Going 9.7 puts you on the short list for fastest humans ever.
As for sub 10, it's still damn impressive. Try running sub 10 yourself. Yeah, we have college kids running sub 10 occasionally but 9.99 can still get you wins on the Diamond League circuit. Even 10.0x can, depending on the conditions.
Last thing I"ll say is, if you can run under 10 seconds for the 100m as a human being, you are a demigod. It is more impressive than running sub 4 in the mile, which is also arguably demigod tier.
It is only just over 7.3 seconds faster than the average 100m pace Bekele ran for his 2:01 WR in the thon. And these runners are not even running for a quarter of a percent of what Bekele is running.
I agree. To get an idea of how fast 9.9 is, consider that Tyreek Hill, generally considered one of the fastest NFL players ever, ran a 9.98. It’s hard to name another NFL player who was run under 10. It’s the kind of speed that is very very rare, drug enhanced or not.
The number of countries who have a sub 10 guy is very small. It just doesn't seem like a bit deal because America is super deep with sprinters. Someone running sub 10 is on the short list to make the olympic final, as long as they get there. Whoever gets 4th at the US olympic trials would be good enough to contend for a spot in the final but they'll be sitting at home instead. Kind of like the 4th best Kenyan in the marathon who will be sitting at home even though they're better than most of the people running in the olympics.