Factor investing has been mainly a domain of relatively large investors that engage asset managers to design a certain strategy and implement it.
Large ETF issuers have done a great job to provide a broader audience of investors access to this investment style by issuing actively managed ETFs in that area.
Vanguard even steps up competition by cutting fees:
Vanguard mounts new European challenge with low-fee funds (by Financial Times)
However there are still ETFs missing that allow access to multiple factors at the same time.