Long before people were talking about factor investing, there was an interest in socially responsible investing (SRI) filters. In my practice, clients have been looking for environmentally friendly investments since long before the 2008 crash.
There were few options available at the time. Most were in the form of mutual funds and they were usually bought by the client, not sold by the advisor. Further, clients usually took the initiative to ask about SRI: they would ask if we could help them invest responsibly, and then we would look for product.