EasyMesh is purely about bringing together disparate devices, and manufacturers can still add unique features and improve specs to help their routers stand out from the pack, the WiFi Alliance's Kevin Robinson told PC World. So, if you have an existing mesh network and one company develops vastly superior security measures, you might replace only the router connected to your modem instead of your entire network. Robinson also noted that EasyMesh is a software standard, so manufacturers can update firmware on existing routers to meet the certification.
Routers that support the standard might have an EasyMesh logo on the box, as The Verge notes, making it clear that they're compatible. However, manufacturers don't have to sign up. Google might decide it's more advantageous to keep Google WiFi a closed shop and ensure owners can only repair or extend their networks with its own nodes, for example.
EasyMesh seems like it'll be more of a boon to smaller companies (at least to begin with) than Google and Eero, who might find it easier to lock buyers in to their proprietary networks because they're better-known brands. Among those supporting EasyMesh from the outset are AirTies, ARRIS, and ASSIA. Eventually, though, EasyMesh could help drive down prices of mesh networks if enough companies adopt it.