Question does mesh (google) have a hardware firewall?

The term firewall is too broad. A company would not be able to sell a box that cost $30,000 if another company could sell it for $200 and they both are "firewall"

It really depends what you goal is. By default even the cheapest home router does the key feature of preventing any attack from the internet. The simple NAT function because it is stupid drops any traffic when it does not know which internal machine to send it to.

After this it really depends on what you want the device to do. Most hardware firewalls are used to protect a server that you have intentionally exposed to the internet. This is not something a home user generally does.