Marvel Studios and the now defunct Marvel Television were always two very separate entities. Kevin Feige is in charge of the former, while Jeph Loeb was tasked by Marvel Entertainment CEO Ike Perlmutter with bringing a long list of different characters to the small screen.
When Agents of S.H.I.E.L.D. launched in 2013, there were reports that Feige was unhappy with the company's decision to expand the Marvel Cinematic Universe on television through the Disney-owned ABC; however, the series still featured some significant crossovers, with Nick Fury and Lady Sif among the most noteworthy guest stars. Then, in Captain America: The Winter Soldier, Marvel Studios revealed that S.H.I.E.L.D was no more - a pretty drastic move when Agents of S.H.I.E.L.D. had only really just started!
From that point on, crossovers were few and far between, and became even less frequent when Feige broke free of Perlmutter and took on 100% creative control of the MCU. Other shows launched on Netflix featuring characters like Daredevil and Luke Cage, but they remained stuck in what can only be described as a "timeline limbo" (post-Battle of New York). That continued in later seasons, and the shows never referenced key events like the superhero "Civil War" to the death of major characters.
Agents of S.H.I.E.L.D., meanwhile, became increasingly standalone in nature, while the likes of Runaways and Cloak & Dagger are barely connected to the MCU. Helstrom didn't even feature any "Marvel" branding prominently on marketing materials, likely due to Feige not wanting people to mistake that mess of a series for what they were doing on Disney+ as Marvel Studios Television.
In today's episode of WandaVision, we're introduced to a book which appears to be the Darkhold. That featured prominently in Agents of S.H.I.E.L.D. and Runaways, but looks totally different here. Of course, it could be something else altogether, but assuming it is the Darkhold, we might finally learn whether these Marvel Television shows are "canon."
Yes, they're set in the MCU, but is it the MCU? None of these TV show characters have appeared in the movies, while a 2015 interview with Feige revealed that he hadn't even watched Daredevil weeks after it had aired. Would someone in control of a world where everything is connected really sit down and start researching all these shows to bring those existing characters into the MCU as we know it?
However, the likes of Daredevil, Ghost Rider, and Deathlok are all too rich in storytelling potential to forever be left on the shelf, so chances are we will see them again. Marvel Studios has just introduced S.W.O.R.D. in WandaVision, but isn't it naive to think that someone will eventually mention that S.H.I.E.L.D. didn't fall and has actually been operating in secret, with an LMD Agent Coulson, time-travelling, outer space visits, and some dude called Mack on a Helicarrier wearing Nick Fury's old jacket? To imagine any of that would one day pop up in The Falcon and The Winter Soldier, for example, is insane.
Wherever you stand on this issue (and there are some who simply cannot fathom these shows not being considered canon), then WandaVision might finally confirm things either way...or continue to leave us in the dark. Many will argue that the Marvel Television shows must be canon because Daredevil is reportedly part of Spider-Man 3; well, even if Charlie Cox is suiting up again (and we really hope he is), do you expect Feige to be beholden to the idiotic creative decisions made in that series? When Iron Fist is finally reintroduced, should he continue to be a bozo who needs a nap after using his powers? Ms. Marvel is an Inhuman, and there are rumblings the disastrous Inhumans TV series will be referenced as just a TV show. The Incredible Hulk was a critical and commercial disappointment with a difficult lead, but the events of that 2008 movie didn't become "just a TV show" in The Avengers when Mark Ruffalo was cast as Bruce Banner.
If we had to guess, Feige will pick and choose characters and actors from these shows for the MCU...minus the baggage. Hopefully, WandaVision makes things clear, but if that book is the Darkhold, and it isn't related to what we've seen on TV before now...well, it's time to accept that the only projects considered canon are those with the Marvel Studios logo in front of them.