When I subscribe to someone's youtube channel through Newpipe, does their subscriber count on youtube go up? Or is subscribing just telling Newpipe to bookmark that content for me, but doesn't tell youtube anything?
The reason I ask is because the subscriber count on youtube could be an underestimate that way.
No it does not increase subscriber count unfortunately. It basically treats that channel like an RSS feed for you. Views are also not counted due to the way newpipe accesses the video content.