The problem with buying the NYT subscription is that you still get the ads. If not overtly, then they are still buried in the content in some sponsored form or another, because this is a large part of how the newspaper makes money. And the newspaper has other agendas too - political, commercial, etc. The Substack model, on the other hand (at least so far) lets you cut out most of the crap - the signal to noise ratio is just so much higher.