The whole event started out with a tweet in May.

Tyler Schultz asked Insomniac Games on Twitter (https://twitter.com/topnotch1210/status/994743495498895360) whether it’s possible to put a „Maddison, will you marry me?” message into the game. It got included, and take a look at the screenshot of the proposal:

Unfortunately, the proposal backfired. Despite the developers helping Tyler, by the time Spider-Man came out, he got dumped three-four weeks ago, and Maddison (or Maddy) decided to choose Tyler’s brother after spending five years with Tyler, who called the text „possibly the saddest easter egg.” He is glad that Insomniac listened to him and worked on his idea, though.

Spider-Man has several easter eggs, including one with the rockets, figured out by SunhiLegend on Twitter. The rockets have serial numbers, weights, and text on them that says „guaranteed to kill spiders.” We don’t have to say anything else about this easter egg, now do we?

#SpiderManPS4 pic.twitter.com/TFCoHUGE4Q

— SunhiLegend (@SunhiLegend) September 8, 2018

James Stevenson, the community manager of Insomniac Games, was previously defending the developers about the alleged visual downgrading, which turned out to be false. He was interviewed by Fandom (http://fandom.wikia.com/articles/insomniac-games-open-to-more-marvel-titles), and he said that working together with Marvel (owned by Disney) drove the team to be better than if they would have been on their own:

„Sure we’d be open to another licensed game. I feel like the question hints at whether there are downsides to it. It’s different of course; you have other people involved who can tell you whether something is on-brand or off-brand, which is different for us than, say, working on a Ratchet & Clank.

But it’s not like we wanted to go too far away from what makes Spider-Man great. It had to be an authentic experience, so in some ways, it’s helpful having extra people around who know the character so well and are pushing you to make things better. Working with Marvel probably drove us to be better than we can be when we’re working on our own stuff.
Marvel wasn’t putting up roadblocks or anything like that; it was more from the perspective of wanting to help us make a great Spider-Man game. Marvel said, ‘here are 50-plus years of comics, characters and stories. Look through all of it and pick what you want.”

Sony’s other teams have also congratulated Insomniac Games. Santa Monica (the makers of God of War) has put Spidey into a scene with Atreus and Kratos, where the dad tried to make his son (or should we say BOOOOOY?) get back in line, and the other image by Guerrilla (the makers of Horizon Zero Dawn) also included Aloy along with Spider-Man and the protagonists of God of War.

Source: Comicbook, DualShockers, WCCFTech, Jeuxvideo-Live

Atreus – “Woah Spider-Man, that looks like a cool fight, we should hang out. You really should meet our friend.”

Kratos – “BOOOOOY!”

Congrats to @InsomniacGames & @MarvelGames #SpidermanPS4 #BeGreater pic.twitter.com/E5fOKkHP0f

— Santa Monica Studio (@SonySantaMonica) September 7, 2018

“More than happy to join the fight! So what are we hunting?”
Huge congrats to @insomniacgames and @MarvelGames on #SpidermanPS4 swinging onto the PlayStation 4. pic.twitter.com/UWv9KYLX2u

— Guerrilla (@Guerrilla) September 7, 2018