Good point. I see this almost on a daily basis with clients. They miss the forrest for the trees. Its dumb to optimize for email capture when people end up hating your brand as a result of it. I remove all pop ups and simply add clear calls to action in different places in the page. They are static components that are part of the layout. The copy is then adjusted to drive invite people to subscribe. I get higher quality conversions. Its not the quantity but the quality of the leads. People forget that.