They chose the right popular media finally after a lot of previous failures like betamax. So choosing CDs for PS1, DVDs for PS2 and then Blu Ray for PS3 helped a lot.
Also they had insane third party support and their first party exclusives are usually really good.
Except first party in PS1 era is not that we can say great or amazing compared to Nintendo and Sega. The strong point of PS1 are on third party , every third party become the first party for them (almost most of them). Saturn was good in Japan but never got strong support in US , N64 was also bad with third party but still got some exclusives deal with third party in US.
The rest i am agree.