How often are you reading a not-that-old article online and the author makes some external reference that has since vanished?

Text: This video summarizes it well. Video frame: This video does not exist.

Sometimes, the web is forever; the web will archive it all for the good of humankind! But just as often pieces vanish, as above.

From that same article:

Online has no boundaries and online can be fiddled with indefinitely. We trade solidity for instantaneous and boundless distribution. It’s a pretty good trade.

Despite the irony, I don't disagree.