The Page Info I see says this:

> article:published-time 2016-10-28T11:40:06+00:00

which is well into the era of 64-bit code.

People are still complaining about macOS dropping 32bit despite the last 32bit hardware having been dropped a decade ago.

Some people (especially game devs) are bizarrely obsessed with 32bit :-/

The LDD3 mentioned is 32-bit era, and 2.6.x kernel, which had a CONFIG_REGPARM to allow passing parameters in registers (because the default was not to do that).