i remember back when Avid decided they were no longer going to offer a Mac version of their NLEs because Apple's new machines were only going to have 3 expansion slots. while admittedly, there were probably a much smaller number of affected users than the Unity decision, it did cause a huge amount of turmoil. urban legend has people dumping their Avid stations on the doorstep of the Avid offices.
Avid survived. Unity will too