Correct but when you use mobile phone opening that link will redirect to imgur and there is an error "Oops! We couldn't find that page" unless you make the browser to request desktop site by opening the settings of your browser then you can finally upload an image. On desktop, this problem/issue won't happen and it is on mobile phones only.
My bad! I am not aware that it is only available on the desktop version. Been tried to check out the upload page with mobile version by myself and encountered the same error message as you. Seems mobile users couldn't upload images without login first through that page unless they use the method which you mentioned earlier
One thing you can do is that you must create an Imgur account if you use mobile phones unlike browser you can directly upload the image even though you haven't an imgur account