Wow. That brings back some memories.
I spent a great deal of my life in middle school arguing with other pokemon nerds on the internet. There was one thing that brought us all together-- finding Mew in the game without Gameshark or Nintendo events.
That truck was a false lead, but many of us believed it. I wasted a lot of time messing with that and other rumors. I must have played through the game a dozen times with different player names to try and find Mew in the Missingno. level 155 pool (which was determined by the letters in your player name). It wasn't until nearly a decade later that someone finally found a real way to catch Mew.
Here is a more recent video using a similar method:
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The only difference between this and the method I used once is I used fly instead of teleport.
I spent a great deal of my life experimenting with glitches like these before and after that. I explored the vastness of the "glitch world" ran every test imaginable with Missingno. and 'M. I had become fascinated with glitches in general, which eventually led to my interest in so-called paranormal events in real life which to me are very similar.