What is the moral message in this joke

The moral message is:

In the joke (or proverb), the oak tree represents someone who is stubborn, proud, or unwilling to adapt. It stands firm against the storm but eventually breaks.

The bamboo represents someone who is flexible, humble, and adaptable. It bends when faced with hardship, survives the storm, and then returns to its original position.

So the lesson is:

• Don't resist every challenge with brute force.
• Adapt to difficult circumstances when necessary.
• Being flexible is not weakness; it can be a source of strength and survival.
• People who can adjust to change often endure hardships better than those who refuse to bend.

In Persian:

پیام اخلاقی این حکایت این است که انعطاف‌پذیری از سرسختی ارزشمندتر است. گاهی اوقات کسی که در برابر مشکلات کمی خم می‌شود و خود را با شرایط وفق می‌دهد، از کسی که فقط بر مقاومت خشک و بی‌انعطاف تکیه می‌کند موفق‌تر و ماندگارتر است. «خم شدن» همیشه نشانهٔ ضعف نیست؛ گاهی راز بقا و رشد دوباره است.