Unless, as mentioned, it had some traction as a cure all around the time of COVID.
This happens periodically and is again happening with vitamin C (which, whatever, getting to any dangerous amount might be physically impossible).
A pretty standard bottle of Vitamin D at 10k IU is 60 capsules/pills/whatever. That's a 2 month supply.
To hit the toxic eventually (77k IU) you would be going through a 2 month supply every ~7 days. To hit the acute toxicity in days or weeks (low end 600k), your going through that bottle every day.
However, every single time that someone mentions Vitamin D, people jump out of the woodwork about toxicity without ever actually bringing up just how much you have to take as if if you take the 400 IU capsule, going one IU over is going to kill you. I'm also pretty sure that a specific group of denialists shouldn't be counted as a reason to scream warnings from the mountaintops every time someone thinks about Vitamin D.
Sure. This is only going to be anecdotal and sparse examples, but this became a thing post-Covid, primarily as a "natural alternative" to vaccination.
Not just random people on random forums, Joe Rogan several times espoused the value of D along with other usual suspects:
"Rogan said he started feeling ill on Aug. 28 and tested positive the next day. He added he began taking his regimen the same day, which apparently included ivermectin, IV drips of vitamins D and C, nicotinamide adenine dinucleotide (NAD) that helps repair cells, and monoclonal antibodies. He said he felt fine the next day."
"Man Vomits For Months After Taking Vitamin D at Almost 400x Daily Recommended Dose"
https://www.news-medical.net/news/20220706/e28098Hypervitami...
https://www.sciencealert.com/man-overdoses-vomits-for-months...
Also unsurprisingly happened more often around this time with infants:
https://www.frontiersin.org/journals/pediatrics/articles/10....