From The Focus - Squid Game: Invitation card's meaning & logo explored
The shapes on the invitation card may be reminiscent of the
PlayStation logo, but it definitely is no reference to the console.
The circle, triangle and squares are actually letters of the Korean
alphabet, written in Hangul, the Korean writing system.
The circle is the letter ‘o’, the triangle is part of the letter ‘j’,
and the square is ‘m’, so side by side, it reads ‘O J M’, which are
the initials squid game in Korean, which is read as
Ojingeo Geim (오징어게임)
It’s hinted in the opening sequence of the show, where the squid game
floor markings in episode 1’s flashback seamlessly transform into the
title.
It may just be coincidence it looks like the PlayStation logo… or maybe not
Even Microsoft noticed the similarity…
There's always season 2...
From https://twitter.com/Xbox/status/1445524219136151564