ChatGPT-3.5 に聞いてみました。

“Owing to” and “due to” are often used interchangeably in casual language, but there is a subtle difference in their usage:

• “Owing to” typically implies a more direct or immediate cause, and it is often used to introduce the reason for something.
• “Due to” is a bit more general and can be used to indicate a cause, but it can also denote an explanation or attribution of something.

For example:

• “The cancellation of the event was owing to the bad weather.” (The bad weather directly caused the cancellation.)　キャンセルの原因は悪天候でした。
• “The delay was due to unforeseen circumstances.” (Unforeseen circumstances were the cause, but it might not be as direct as in the first example.)　何らかの理由で遅延が生じました。

In some contexts, they can be used interchangeably without much difference in meaning. However, in formal writing or contexts where precision is necessary, it’s best to use them according to their nuances.