Sony aren't so clever or so cunning to think such a plan to... I don't know... keep people from playing Shift 2? What's next? Sabotaging future SMS games not to endanger GT5? Now that I think of it they aren't so dumb either.
Sony is primary a console manufacturer, not a game developer. And a console manufacturer makes profit by selling a lot of consoles and having people buy games (disc games, downloadable games, DLCs, accessories, etc) for this console. Also by selling dev kit to third party developers. The only reason Sony makes first party games (like GT5) is to make more people buy the console so that more third party devs make games for their system, more dev-kits sold, more games sales, fueling more consoles sales, dev-kits, games, therefore more profit.
Furthermore games are for having fun. If you imagine conspiracy theories where Sony on purpose ruins a game then you take the joy out of the game.
In my opinion, have a little more patience...
The patch will be released soon, PSN will be back up and the Legends Pack will be available.
And if a game is aggravating you (like GT5 did for me) stop playing, thinking and arguing how it can become better (like I did for GT5).
You will be much happier!
I know you like Shift 2 (like I do) and that the various issues (which every game has) make you mad. I am just saying that you should focus on the good things of a game and have fun. You may think that this is wrong but I believe it's healthier. Games are for having fun! If you have fun overlook the unavoidable omissions or else the omissions will take over the game and you will only see them, therefore ruining the game for you. If the omission, glitches, bugs are so many that you are not having fun, stop playing, bothering and buying future versions. Video games is a chance to take your mind of life's real problems, not fill your mind with more worries and your time with tedious tasks (like grinding...)