I'd heard of SpaceX in 2013, but was skeptical. Then in 2015, my relative who'd started working at SpaceX called everyone to the TV at my grandparents' house, and we watched them land the first booster live.
I knew that finally spaceflight had a bright future again.
I see a lot of people sharing stories so I think I might as well. The first SpaceX launch I watched live was Jason 3 on January 17 2016. The fifth landing attempt and the first one following the first successful RTLS a month before. We didn't get this video until the day after launch. This was the point where I really got interested into spaceflight as a whole. I have highly mixed feelings about the state of the company just over ten years later as they have gone public today but it's been one hell of a ride, that's for sure.