Divesting assets related to fossil fuels is irrational and likely destructive of the values that prompt it. Shares already issued are merely changing hands, not depriving the issuing companies of any capital. Further, the people or institutions to whom the divested shares are sold are likely indifferent or even hostile to the value system of divestment zealots, so the shareholder/agent voting pressure on corporate governance could actually diminish.
Also, assuming that companies do not seek, produce, market, or use fossil fuels as a hobby or as an obsessive-compulsive exercise, their activity simply reflects the fact that people need or want their products. Why leave consumers off the tantrum-driven hit list?
To be logically consistent and to maximize the virtue-signaling aspect of divestment, therefore, Princeton should be equally committed to refusing to admit, hire, or retain anyone who drives a gasoline-powered car, heats with anything other than lunar power, has a polyester shirt or blouse in the closet, uses a solar panel that has any fossil-fuel DNA in its production chain, keeps their leftover kale-and-quinoa salad in a plastic container, assimilates their faux-moralistic view of the world through plastic-lensed and -framed eyeglasses, or uses a plastic-cased pen to sign divestment petitions, and so forth.
If the Fates are kind, these trendy episodes of outrage will eventually self-destruct like a lithium battery exposed to air, but in the meantime, they are pathologically interesting.