How long have you been using Macs? They USED to release a new OS every year, and at $129. Then they slowed that down, to every other year or so in 2006.
Just looking at OS X:
Public Beta Kodiak, September 13, 2000
10.0 Cheetah, March 24, 2001
10.1 Puma, July 18, 2001
10.2 Jaguar, May 6, 2002
10.3 Panther, June 23, 2003
10.4 Tiger, May 4, 2004
10.5 Leopard, June 26, 2006
10.6 Snow Leopard, June 9, 2008
10.7 Lion, October 20, 2010
10.8 Mountain Lion, February 16, 2012
So you can see they had a major revision every year (two in 2001) since the release of OS X, until they got to Leopard. Then it was every two years. Now it's going back to every year. And at $29, I don't see a problem!
I've used every version of Mac OS starting with 7.1.2. I skipped the public beta of OS X, but installed Cheetah the day is was released. Had to do a lot of dual booting back then.
In the time between 7.1.2 and OS X 10.0, I've used 23 different versions of Mac OS, ending with Mac OS 9.2.2.
I bought a PowerMac 6100 in 1994. So in the seven years from that machine running 7.5 to Mac OS X 10.0 in 2001, Apple released
21 OS updates. That's three updates a year!