This is a tough one. The easy answer is to add an option to paginate. In reality, there are a bunch of UX challenges we would need to solve in order to this, though. What happens when you try to paginate a project that doesn't easily break into pages (misaligned bottom borders of tables and graphs, for example)? I'm not saying that we won't do it, simply that it's more complex than it may seem. We definitely will not force people to paginate, which means we need to figure out how it works as an option.
I tried downloading a long report in PDF but my data is not being compressed into one page, it is shown in the same way as on the workspace. Could you check maybe your printer settings are affecting the output?