A lot of creatives have a hard time understanding the product side of art. Games are far more products like movies than they are "art". There have been a bunch of recent examples lately that showcases the minds of masses. Spiderman No Way Home did supremely well by giving the masses what they wanted, and not straying too far from the marvel formula. Sonic the Hedgehog Movie had a awful original art direction. The fan…
Says whom? You demonstrate your points by showing that blockbusters make money, which says nothing about whether they are art. They're entirely different dimensions of the same work, and hard to compare. Obviously the accounting department will have a different point of view than the creative director.
You're also arguing that people making new films on an existing franchise should stick to giving the fans what they want. But who's to say the fans even know what they want? They might not care, they might be mistaken, they might misremember things. For example, people clamoring for World of Warcraft Classic or a back-to-the-roots Sonic game back in the day weren't really hoping for a product per se, but rather to go back to a time when the product was more culturally relevant (and they were younger).
A new direction can also capture a new audience, which might make fans negligible. For instance the Star Wars prequel are still divisive but a large, younger portion of the fandom likes them very much.
And what fans are we talking about anyway? You give Spider-man as an example. But there have been thousand of pieces of Spider-man media, with wildly different art styles and tones. Which one is "what the fans want"? Disney went with the Marvel formula precisely because it's a lowest-common denominator style of film, accessible to non-fans.
And finally another obvious problem with your thesis is that nothing new can be made if it is required to give to the masses what they want for sure. Almost by definition, it is unknown whether any new concept, style, tone, or property are what people want. At the same time it is known that the public at least somewhat values originality, so companies take risks and release films such as Pirates of the Caribbean or games like Assassin's Creed.