It's all the people you'd expect, some purpose-built REITs, big investment firms and private equity, Blackrock, Blackstone and other wealth management, the larger investment banks and the commercial mortgage paper owners are also directly invested (double dipping just like we saw in 2008, where banks would buy mortgages and also leverage those mortgages with derivatives)
Many of them are some of the companies that wax lyrical about remote work being bad and are often featured in articles. Submarine PR is absolutely rampant alongside "native advertising".