I'm surprised the article barely mentions Vitamin K, which is needed along with Vitamin D - D to mobilize the calcium and K2 to put it into the right place. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5613455/
There is a lot of misinformation on the web around Vitamin D, such as that even high amounts (>= 5000IU) are tolerable and safe. After a blood test showed me Vitamin D deficient, taking 5000IU (that size is readily available over the counter at my grocery store) daily gave me disturbing heart palpitations, which I didn't realize were related to Vitamin D until after thousands of dollars in tests showed my heart to be perfectly healthy. It wasn't until I had slacked off in taking the vitamins and then started taking them again that I discovered the connection. Apparently magnesium has something to do with it, but IANAD. (I was not taking magnesium supplements at the time.) I can tolerate 1000IU occasionally, but people need to be aware that not everyone tolerates supplements (especially high doses) the same.
I was happy to see the article you linked to above only claims Vitamin D is considered safe up to 4000IU. Although IMHO, after my experience, anything over 1000IU should require a prescription. Of course nothing would stop people from taking five 1000IU OTC doses to get 5000IU, but I think most people know better than to take five of the same type of vitamin daily without talking to their doctor first.