There's a proven way to do this: opt-in instead of just assuming everyone wants this and can opt-out otherwise
Edit: not sure why I'm being downvoted; it's true. If someone has to opt into using your product you're starting out with friction from the gate which is difficult to overcome.
Morally it's questionable but trying to create a grow a product it certainly shouldn't be surprising. Gitter does this and the HN crowed seemed to really like it last I saw it posted.
I don't want anybody to make those decisions for me. Just because I set up a public profile on one page, does not mean, that I want others to scrape data from it and use this for their purpose. Of course, stuff like this happens all the time, but it doesn't make it right.