It still needs `f_jxl` in parameter. Automatic support has still not launched as per this article's last paragraph: https://cloudinary.com/blog/jpeg-xl-how-it-started-how-its-g...
You dont need to use the f_jxl parameter. e.g. https://res.cloudinary.com/demo/image/upload/c_scale,w_500/f...
And can all be handled via srcset.