Perhaps he means that after his choosing the road his life had taken another upturn

Meaning of the phrase "made all the difference":
The phrase "made all the difference" refers to a significant impact or influence that has changed the outcome or the course of events in a particular situation. It implies that a particular decision, action, or event has had a crucial effect on the final result, leading to a significant change in the outcome.

Explanation:
- Significance of the choice: In the context of the poem "The Road Not Taken" by Robert Frost, the speaker reflects on a decision he made to take a less-traveled path, which "made all the difference" in his life. This choice had a profound impact on his journey, shaping his experiences and defining his future.
- Unique path chosen: By choosing the road less traveled, the speaker deviated from the conventional path taken by others. This decision symbolizes individuality, independence, and a willingness to take risks, which ultimately set him apart from the rest.
- Impact on the speaker's life: The decision to take the less-traveled road led to a series of experiences that shaped the speaker's character and perspective. It allowed him to explore new opportunities, face challenges, and grow personally and intellectually.
- Reflecting on the outcome: The speaker looks back on his decision with a sense of satisfaction and fulfillment, knowing that the path he chose "made all the difference" in his life. It represents a pivotal moment that altered his course and defined his journey.
- Lesson learned: The phrase "made all the difference" conveys the message that even small choices can have significant consequences. It emphasizes the importance of taking risks, following one's own path, and embracing the unknown to create a fulfilling and unique life experience.