10.4 was looooong ago, man, and yeah that's perfectly fine (10.5 too), it's 10.12 now apparently ?
Now I only barely interacted with whatever is the current release, but even some basic stuff (resizing windows and shit like that) really threw me off. That's a very shallow impression but I had earlier gripes (price, closed environment, the whole "you can only add stuff on iPhone via iTunes sync") and overall I don't see me coming back to Apple unless it's mandatory for work.