Some versions of some browsers turned DNT on by default. Respecting DNT in this instance would have always made this flag a choice by the user. There is still

Some versions of some browsers turned DNT on by default. Respecting DNT in this instance would have always made this flag a choice by the user. There is still room to argue that the user's choice was to install a browser that made DNT the default option. But it's a moot point, since the sort of web services that were in mind when DNT was proposed largely ignored it. They never set the evil bit in their responses, either.