Aside from making a lot of great games and securing a lot of good content via moneyhatting or due to Nintendo dropping the ball, I think it's also being persistent. Sony continued even after the financial disaster that was the PS3.

This one was harder for me to answer. I can see 2 reasons:

1) Good relationship with third parties. It's quite clear developers wants Playstation systems to be a success. Sony designs their hardware based on what the industry and other publishers would likely want a Playstation hardware to be. From standardized controllers to certain level of computing power to process the newest graphics. Their relationship is good enough to secure even GTA VI being released on PS5 1 year before the PC release. Japanese developers kept their games exclusive on Playstation for as long financially viable. This speaks volume on what publishers think of Sony and Playstation 

2) Taking every market with care (except Japan* where they decided to abandon when killed their portable line). Nintendo is dogshit when it comes to availability, distribution and pricing outside America, Europe and Japan. Microsoft is better but lacking in branding. But no company saw and treated Europe and ROW with the same care and importance as Sony. Playstation has currently 5/6 of the best selling consoles in ROW. Those markets loyalty has secured Sony long-term stability in console bussines, in the same way Japan secured stability for Nintendo's bussines 

* I'm putting an asterisk here because even Japan was not dropped so deliberately. They moneyhated tons of Japanese third parties during PS4 life, it's just their efforts to cater Japan were unsuccessful. PS5 is where they really given up

This too. They also sold both PS2 and PS3 for the lowest possible price for as long it was possible. PS3 after 3 years in the market was like 300 USD

PS5 is the only console they kept the pricing high in hopes of getting higher profit margins

Hardware that customers want to buy and developers want to make games for.

IMO - Mostly because Sony got it so right with the PS2. They'd have probably lost interest in the market if the PS2 hadn't worked out. the way it did...

I think the key has been the combination of solid first party(this gen not withstanding) and solid third party. Something for everyone. An easy solution if you don't want to worry about what you're going to get. Even if all the exclusives are not to your particular taste, you're good. They managed to build this trust over the years and become a household name next to the legendary Nintendo in a very challenging field.

3rd party support, no one comes close to seeking partners the way Sony does.

This is also their biggest weakness because these companies don't work for Sony ie once they seek alternatives to making money on other platforms creating competition for PS. As 3rd party support becomes more widespread, the audience for those games spreads out and the platform with the most of this audience becomes the platform with the most to lose. This is why Sony makes those marketing deals, it's to keep the audience buying on PS. Microsoft buying CoD for example was such a big deal because Sony knew the marketing deal and it's advantages would end but Microsoft isn't dumb enough to act like the majority of CoD's audience is on PS.

If Sony make a teletubbies or Dora Explorer PS5 exclusive game, true to their TV shows identity, you definitily would say the same shit lol

Europeans even though thus treat us like the region they hate the most. We kept them alive as a console brand through their darkest hours and we get shit on them for it.

Depends. Is Dora the biggest game on PS5? Because right now, the biggest on S2 is DKB, which is basically Wreck It Ralph in video game form. On PS5, it's either Death Stranding 2 or GOY.

Nick Jr. vs HBO.