I believe, that the GP comment is too dismissive, but it is true. In 2005 when the dominance of IE started to dissolve it was not the best move to develop for a single browser. Though people still did it.
Today we see a rise of ARM on desktops, developing for x86 excludes Mac users, but the situation moves in a direction when exclusive x86 software will exclude an assortment of users of different OSes who chose to buy ARM desktop/laptop.
But I completely understand the choice made by the author, to use vector extensions on two (or three? RISC-V?) processors would be a much more additional work. The project is FOSS so anyone can jump in and add support for ARM vector extensions. Hopefully it will be easier then to write it from scratch, because you can compare intermediate results bit to bit, and catch mistakes red handed.
Today we see a rise of ARM on desktops, developing for x86 excludes Mac users, but the situation moves in a direction when exclusive x86 software will exclude an assortment of users of different OSes who chose to buy ARM desktop/laptop.
But I completely understand the choice made by the author, to use vector extensions on two (or three? RISC-V?) processors would be a much more additional work. The project is FOSS so anyone can jump in and add support for ARM vector extensions. Hopefully it will be easier then to write it from scratch, because you can compare intermediate results bit to bit, and catch mistakes red handed.