What does it mean to be a 3000-year-old flat peach and a 500-year-old spiritual tree?

Flat peaches last for 3,000 years, and Lingchun lasts for 500 years. That is to say, flat peach trees only bear fruit once every 3,000 years, and Lin Chunshu only bears fruit once every 500 years. Both of them are magical fruits that exist in myths. In fact, they don't exist. Some things in life are hard to get and cherish.