Basically, the summary of that link is you now have to activate your new Razer products online and accept their licence agreement that allows them to gather data from your computer. If you don't, your mouse will still work as a plug and play, but you won't be able to access any of the features that make your fancy new mouse matter. Just to make sure this was a real thing, I went to Razer's website and sure enough, under the system requirements was the following:
Razer Synapse 2.0 account registration (requiring a valid e-mail address), software download,license agreement acceptance, and internet connection is required to use full feature set of product and to receive updates.
Awesome. Guess I'm never buying a Razer product again. I'm kind of shocked they would even think about pulling something like this.