Yeah, that’s close and if it impacted, depending where there would be a lot of damage and possible loss of life, again depending on where it hit. But ‘’planet-wide destruction’’ from something the size of a bus? No. A mile or more across, yeah, definitely would be a very bad day on Planet Earth but not something on the order of this object.
I believe his reference to planet-wide destruction wasn’t referring to a 25 foot object; he was pointing out that an object large enough to cause that kind of damage could show up with no or inadequate warning, just as this little dust speck did.