To clarify on behalf of Canon - the i9900 was released on 2004 and OSX from Apple was released on 2009. So that is five years of support for a $500+ printer. A printer which has expensive color cartridges, printheads, etc.
The "15 years" is a red herring - Canon only supported the printer on MAC for five years and had/has no intention of looking back.
Thats OK, I purchased an EOS M and they did one release of firmware before discontinuing the camera all together.
That is your "Canon Community". Yay, NOT