Eh. It doesn't even do that.
Vitamin D and Calcium from US Dept of HHS
or A Randomized, Controlled Trial of Vitamin D Supplementation upon Musculoskeletal Health in Postmenarchal Females. "Despite improvements in 25(OH)D status, treatment with vitamin D2 was not shown to increase mineral accretion, bone geometry or strength, muscle force, or power. "
And as a single point, I've been quite D-deficient (<10) for 6 years, and my bone density is sharply up, not down.
And the folks who take it and think they no longer have colds need to worry about whether or not the lack of symptoms just means they've just totally suppressed the immune response to the common cold. Reversing Bacteria-Induced Vitamin D Receptor Dysfunction to Treat Chronic Disease: Why Vitamin D Supplementation Can Be Immunosuppressive, Potentially Leading to Pathogen Increase
Vitamin D2 is useless
The medical scammers always run their “studies” with useless synthetic vitamins, even though they know better.
A healthy population will bankrupt the scammers.