Although Google did come up with the original specification their influence over the IETF specifications is not overarching nor absolute; gQUIC is substantially different from IETF QUIC which has caused Google themselves to have implementation and interop issues in their deployments. OS vendors, CDNs, academic researchers, and individuals have all contributed to the resulting specifications that have emerged in a standards body that is by far the most open as the requisite to participate is a functioning email address. All matters and decision making are publicly available for observation and scrutiny.
There is no requirement for people to implement this protocol and it won't be appropriate to every use case that exists today. TCP, UDP, HTTP/1.1, and HTTP/2 are not going away - all continue to undergo standardisation, research, and new implementations.
(Disclosure: I'm not a Google employee, but I have participated in the QUIC and httpbis working groups)
There is no requirement for people to implement this protocol and it won't be appropriate to every use case that exists today. TCP, UDP, HTTP/1.1, and HTTP/2 are not going away - all continue to undergo standardisation, research, and new implementations.
(Disclosure: I'm not a Google employee, but I have participated in the QUIC and httpbis working groups)