It's because they can't control the data coming from your phone....

It's because they can't control the data coming from your phone. They can control it coming from their servers. As far as I can tell this tech is not overly fancy or hard to implement they have just done a very good job of implementation and making a product out of it. If I was able to setup this VPN on my own router and be assigned a static IP that I was the only user of I would pay up to $40/month for this.

As far as I can tell it's people jumping ship that have no idea about the tech or how it works. They are just seeing bad speed tests on some sites and bailing. All you need to do to test is actually USE it!