Strange. The TekWiki states that the 465 scope was introduced to the market in November of 1972, and the TekScope journal (fall 1972 edition) supports that. Atari's PONG was already up and running at that time, with a first test unit installed in a bar in August and full market launch in November.
So the 465 can't have played a role in "inventing" or "designing" PONG. Maybe it was used in ironing out some final glitch, or in developing later spin-off versions of the game?
Al Acorn's letter states that the scope was introduced in 1970, but his memory does not seem to be correct in that respect. The letter also states that the scope was bought "so I could design video games
like Pong". I wonder whether he chose that wording deliberately, since he did
not use the scope on Pong itself, but on later games only?
https://w140.com/tekwiki/wiki/465https://w140.com/tekwiki/images/7/7a/Tekscope_1972_V4_N5_Sep_1972.pdf