Did I wake up in the mid-18th century?
It's not like deism has vanished, just a niche position to hold in this day and age.
A very niche position. It seems to have been largely replaced by pantheism or the amorphous group of people calling themselves "spiritual but not religious".
There are probably some interesting historical and sociological conclusions to be drawn from this shift, since pantheism is at least nominally the exact opposite of deism.
I wonder how much of it has to do with the migration of Eastern religions to the West, especially Sikhism.
It's more about the rise of literacy, environmentalism, improved communication and translation, and globalization.