Feel free to email me! (author)
Well, for a new executable and dynamic library format, the computer language syntax complexity and its runtime complexity do matter A LOT, c++ is massive pain, and since, if I am not mistaken, sqlite is going microsoft rust, that's bad omens since microsoft rust syntax seems to be now as brain damaged than c++ syntax... but with an even worse runtime (unless all that is not actually true, I have not checked). That said, ISO f*cked up C with things like '__thread' which requires some level of OS support.