After Avengers: Endgame featured time-travel and alternate timelines, Spider-Man: Far From Home introduced us to the idea of the "Multiverse" (only to later reveal Mysterio as a fraud). However, it wasn't until Loki that we got to fully explore the concept of Variants and different realities, and the finale obviously opened the door to the true Multiverse becoming a part of the MCU.
Spider-Man: No Way Home takes full advantage of that premise, but how much of what we saw in Loki impacted the threequel? Not a huge amount, as it happens!
"We were already down this road when that 'Loki' finale happened," Spider-Man: No Way Home co-writer Erik Sommers tells The Wrap, admitting that it wasn't the original plan for that Disney+ show's finale to sync up with their movie. "We all felt like, this really helps. This is great, because it shows that there is trouble in the multiverse."
"Whether certain things that were happening in 'Loki' line up in terms of the timeline exploding and is that the same time that Doctor Strange is casting the spell, I don’t know," his co-writer Chris McKenna adds. "There is, I’m sure, the Marvel talking points to that. But we were aware of a lot of the different things that were going on, and could we draw on those, how it would be affected by this thing, but ultimately we had our own giant story bear to wrestle with."
Marvel Studios no doubt had an idea of how Spider-Man: No Way Home could connect to their larger plans even if the writers didn't, and the fall of the TVA and rebirth of the Multiverse is probably what led to those Variant villains arriving in the MCU, anyway. That's not something Sommers and McKenna really needed to touch on here, though we're sure Doctor Strange in the Multiverse of Madness will.
Either way, it feels like the MCU is going to take us to some wild places over the next few years...