That's not the point, the point is an instant is not a date. And common ways of getting the date from an instant are likely to give you the date of the instant interpreted in your current timezone for your computing env (which is often what is wanted such as when displaying for a user), so when you extract the date portion, it is not the intended one. So it's not that there's an easy right way of doing it, of course there is - but there are also easy wrong ways which also seem obvious.

Also, forget about the receiving side, you're also assuming that the sending side meant the date for the instant as at offset 0 instead of in their own timezone (which is probably how the instant is being displayed for them). From experience, that's not a safe assumption - witness any instant meant to mean "today's date here and now" derived from a now() call alone or truncated to have 0 time parts (in current time zone!) - I see that attempted a lot. Way too error prone especially when you don't control both sides.