I think that's a valid concern although I don't see results as dire as what you're describing.
My impression is funds that invest in energy products/services are beginning to diversify into renewables. These people spend their days watching the markets in an attempt to anticipate changes. And I think the drop in demand for oil will be gradual; not sudden.
But I do agree re fossil fuels; esp. oil. Oil has been a world-wide exchange medium for several decades, but that is about to change. Coal, IMO, is on its way out. I just reviewed a potential investment (energy sector) where the group was clearly moving out of coal since more and more energy producers (aka utilities) are switching plants to gas. These utilities also seem to be looking at blending renewables into their grids.
And I know there are plants that are going to use coal, but I think those are meant more for PR than any actual trend.
So, again IMHO, anyone invested heavily in fossil fuels should be watching the markets.