Pretty sure I found my answer.
Credit: CNET
Thank you,
Shane
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If you're wondering if you might just use a single Nest Wifi Pro device as your main router, with the earlier-gen Nest Wifi Points added in to bring the smart speakers back into the mix, then I've got some bad news for you. Unlike the original Nest Wifi, which is fully backwards compatible with the first-gen Google Wifi mesh router, the new Nest Wifi Pro isn't backwards compatible with anything. That means that you can't use it with older Google Wifi devices, nor can you mix and match with second-gen Nest Wifi hardware.
Sources at Nest tell CNET that the new system was designed to make full use of the 6GHz spectrum that comes with Wi-Fi 6E, which means that it isn't a good fit to slot in with older hardware that can't access the 6GHz spectrum at all.
"To do that with Google Wifi and Nest Wifi generations that don't support 6GHz was not going to be a good experience for users," said Ben Brown, Google Nest's director of product management for energy and connectivity.
That lack of backwards compatibility makes Nest Wifi Pro a less appealing option for existing Nest Wifi users who might have been hoping to upgrade their mesh network one device at a time. Instead, to make the upgrade, they'd need to replace all of their mesh devices at once, which is an expensive proposition.
