I just close it immediately without reading it like the internet has trained me to do with literally every modal. You want my attention? Put some call to action in the text I'm reading. A modal popping up mid-content asking for my email is just a good way to signal to me that you don't value your content and that you just wrote it so you can get my information. And sorry to those folks, I don't even read it.
FWIW, that’s just a Substack feature. It’s not like the authors all got together and decided they all wanted to make a modal pop up on scroll and interrupt your reading.
And that's fair, I understand that but they do still choose to publish there instead of their own blog. My opinion on that site is kind of agnostic of the owner of the problem it's more just that I'm not going somewhere knowing that is going to happen when I do.
I haven't really looked, but I suspect some of the built-in uBO filters might work too.
Please no. In-article advertisements and link blocks are a plague on online publishing.
I'm sure Substack will eventually do this however. In the early days they didn't have a nagging modal. Over time they'll go full Medium.com and straight up hide free articles behind a signup/subscribe.