That was a tiny meteor.
The meteor that created the extinction event at the K/T boundary was 5 miles across. It was about the same size as Mt. Everest. For the brief moment that the meteor touched the Earth it was the tallest mountain on the Earth. The one that struck Russia just recently was only about 20 meters across. They aren't comparable.
The K/T event wasn't even the largest impact. There were larger ones, and numerous ones.
The reason I like this argument is because it really sort of covers all the bases. It doesn't rely on dating or anything - though that can help the point - but just on what we know about meteors.
We have a bunch of craters. The only thing we know of that makes craters like this are meteor impacts. From what we know, we can make pretty safe estimates on the destruction such impacts would create.
If the Earth is old, that's not a big deal. These sort of impacts rarely happen, and the reason we find so many is because the Earth is old. One or two happening every few million years isn't enough to cause global extinction. The Earth has time to recover, it's fine.
If the Earth is young, though, that's a problem. Clearly, the Earth hasn't been bombarded by these meteors since humans started recording things - it's not mentioned at all in the Bible, or any ancient text. What's more, if you take Genesis literally, you have to shoehorn in these devastating impacts somewhere. It couldn't have been before the fall, because that was supposed to be paradise. It couldn't have happened before the flood, because that would have killed what few humans were around at the time, and there wouldn't need to be a flood. That leaves you with it happening during the flood, and having all those impacts in a single year would kill Noah and just about everything on the planet except for a few bacteria.
The only creationist explanation I've seen is trying to argue that all those craters are not, in fact, craters, they're created by some strange event in the Earth, but even the creationist I read trying to make that argument admitted it was sketchy, at best.