Thanks for your understanding and fair discussion :-) On this point:
> This collecting user data to influence their behavior...
I think that's a really negative and cynical way to look at what we and other FOSS projects are doing. Here's an example of what we can do with some basic website analytics data: we can put a banner on the download page saying "Made by the community - you can be a part too!". The banner links to a "Get involved" page, encouraging people to join the project.
Then, with analytics tools, we can see how well that works. We can do A/B testing by having some download pages with the banner, some without, and see which ones help bring new people into our FOSS community. This is really useful and good for us all!
Now you could say this is about "influencing behavior", and in a super pedantic sense it is. But again, when people talk about websites "influencing behavior" the big topics at the moment are Russian troll farms, Cambridge Analytica etc. I don't think it's fair to use terms like that when we're not trying to play mind games with anyone!
> That slippery slope has Facebook-like mind manipulation at the end of it
Ah please, we're just a small non-profit entity organising a FOSS project and trying to make a website that encourages people to get involved. The "slipperly slope" argument doesn't work well. One thing doesn't inherently lead to another. With that argument, drinking beer leads to other substances which leads to X Y Z... Nah, I've been drinking beer for years and haven't touched anything else. Beer is great enough :-)
Really, if you have a genuine fear that some LibreOffice community members using Piwik to improve the site could lead to "Facebook-like mind manipulation at the end", please do join the website list, put forward your points and let's deal with it! But having been involved in FOSS projects for over 20 years, I don't think that's a concern. People are just trying to do the right thing :-)