This is true. Sony doesn't update software much.
Then again, Fuji (which is seen as the example of firmware updates) updates often include things already found in Sony cameras (reliable AF, easier fly-by-wire MF, focus peaking) among other bug fixing updates. When I had a NEX 7, the biggest single improvement on the one update it received was the expansion of the bracketing function (to + - 1, 2 and 3 stops if I dont badly remember), turning off the MOVIE button and the improvement of the flexible spot focusing thing (I really dont know what that meant)
I don't know about the other camera updates or their frequency. The first time I updated anything was my Canon 5D2 and the update was something it was much asked for: manual control of video and later manual control of audio input on video.
Ray is right, though, if there is something you don't like about a Sony cam, do not expect them to provide a firmware upgrade.