Dreams involving encounters with strangers can often symbolize different aspects of our subconscious thoughts or feelings. In your case, dreaming about a man standing on the sidewalk may represent an unknown or unexplored part of your life or emotions. The fact that you approached him could indicate a curiosity or a desire to confront something unfamiliar or potentially threatening.

The connection you made years later when seeing the photo of the man being described in a troubling situation could evoke feelings of anxiety or fear about safety and trust in the world around you. It's common for our dreams to intertwine with real-life experiences, leading to feelings of déjà vu or a sense of foreboding.

While it might be tempting to view this as a premonition, it's important to remember that dreams often reflect our inner thoughts and external influences rather than predict the future. It could be a coincidence, or it might serve as a reminder to remain cautious and aware of your surroundings. Reflecting on any anxieties or fears you may have regarding safety or the unknown could provide further insights into this dream and its lasting impact on you.

If these thoughts continue to trouble you, consider discussing them with someone you trust or a mental health professional for deeper exploration.