Warm wine and hot wine often appear in winter and autumn, because these two seasons are colder. The weather in ancient times is colder than the present, and the heat preservation measures and cold protection measures are not as good as modern ones. Therefore, many people in ancient times chose to use gods to resist the cold and warm their bodies. Warm wine and hot wine can increase the temperature of wine.
This is completely unnecessary. The warm measures we wear are also in place, and the weather is not as cold as it was in ancient times. You don't need to drink to resist the cold.
Another possibility is that warm wine was used in ancient times to further make the wine smell mellow. Of course, the technology now is superior to that in ancient times, and the brewed wine is more mellow, so there is no need to warm the wine and scald it.