idk about the author, but when i was younger, some people's pedantry and pettiness over grammar / capitalisation / more casual chatting got me to switch sides and deliberately stop using it as much. now it's also an aesthetic preference
i think there's potentially a valid point about accessibility concerns, but blog posts, chatrooms, and internet comments are also very informal modes of discourse
also, there are no spelling mistakes in my comment. perhaps consider learning about how words are spelled in british english vs american english? :)