Because Jing Ke stabbed Qin, he was praised by the people at that time! Even with this poem, people began to admire Jing Ke. Through this poem, they were moved by Jing Ke's generosity in dying. Over time, this poem and Jing Ke's stabbing Qin itself became an organic whole.
Finally, the level of this poem itself is no longer important. What is important is that it represents a phenomenon and a new emotion.
Today, when people say "Jing Ke stabbed Qin", they immediately associate it with the poem "A strong man is gone forever". As soon as we say that "a strong man will never return", people immediately react to the story of "Jing Ke stabbed Qin".