This quote from the article you linked to sums up my viewpoint well:
> If it does prevent or cure coronavirus, great. If not, the worst that will happen is you'll have slightly better bone health.
Taking Vitamin D daily is like taking Vitamin C daily. Who knows if it actually helps, but we know it doesn’t hurt, so why not.
Edit: (as mentioned by commenters below, obviously don’t swallow more than the recommended dose on the bottle)