I can't believe all the cynicism here, I would _love_ a free VPN from a reputable company. If Google wants to anonymize my data and use it to understand what websites are most popular, that's fine with me.
Google does not give out free lunches. You are always paying for their services in some way, and that is usually by them mining your data and selling it to other companies. What possible motive would google have for operating a free proxy service? The sheer goodness of their hearts? Concern for your privacy and safety? Respect for the open web?
Everything google has done in the last decade shows very clearly that their motives are never good. At some point, you have to realize that the dog that keeps biting you will never stop biting you.
I too would love a free VPN from a reputable company. Unfortunate Google isn’t one.