Why would Ubuntu as a generalized statement recommend its 64 bit “flavour”?
As far as I understand a 64-bit OS can only be installed on a 64-bit hardware (CPU), i.e. 32-bit and 64-bit OS can be installed on a 64-bit hardware, but only a 32-bit OS can be installed on a 32-bit hardware (regardless of the amount of RAM available).
You can see this on the download site:
I understand the difference between 32-bit and 64-bit, and I see the pros and cons. For users with a 32-bit hardware this is not a question of choice. Recommending a 64-bit OS without taking into account the hardware is like recommending petrol over diesel and neglecting the engine. The download site does not check for 64 bit processor hardware, and if detected recommend a 64-bit OS, but recommends a 64-bit OS to all users (with more than 2 GB RAM).
It has been stated that ”manufacturers don’t really make 32-bit systems any more” (Dalton), and that “almost all chips in recent history are 64 bit” (oldfred). This is true at least for processor families in TOP500 supercomputers. So this recommendation simply reflects a trend in industrial production?