Closed source means users unable to verify your marketing claims about tracking. Privacy conscious users like myself would prefer an open-source commenting platform, even one with tracking, since we could verify how it worked (and also take it a step further and circumvent tracking by examining the source).

Also, what's to prevent a provider from double-dipping? If you can sell the product plus your users data you can presumably generate even more income. For example, mobile phone carriers sell monthly plans to users and some sell users location and usage data (usually "anonymised") to advertisers.

I don't mean to imply that you are doing these things, or that you ever would, but without independent verification by a trusted third-party, all the users have to go on are your marketing claims. What's your plan for dealing with sceptical users?