While you are likely correct about the origin of TSBs, that's NOT what they are today.
In all fairness, the reason that Technical Service Bulletins became so interesting to general consumers is because manufacturers have a tendency to not admit problems (and issue recalls for them) unless there's a threat of government intervention (such as a NTSB mandated recall.) Likely, this is done to try and save money. Instead, they put out these TSB's and claim the issue only impacts "some" vehicles.
A perfect example is the CX-5 2014/2015 touch screen radio issues with USB and Bluetooth. It's a problem on 100% of the touch screen units installed on every single 2013 CX9, and 2014/2015 CX5/Mazda6. However, Mazda has only issued a TSB for it.Then there's also the tendency of the dealer service departments and/or manufacturer to claim that something "works by design" unless there's a TSB or recall issued for the item. So, consumers have to monitor the issued TSB's to know when they can bring the problem to a dealer to be fixed.
Finally, from a CONSUMER point of view (at least in the US) of the difference between a recall and a TSB is that a "recall" usually allows a "free" repair outside of the warranty period. On the other hand, a TSB usually will only be fixed for free if you're still under warranty (or have documentation proving that you complained about the issue while still in the warranty period.)
