I mean the entire concept of a Cinematic Universe is a direct result of the MCU, which largely is a creation of Disney. We can argue about the details but when you hear Cinematic Universe, the MCU is what people think of first.

There are plenty of reasons to hate Disney, and there are plenty of remakes and sequel that are terrible and uncreative, but those are the safety money projects. They get made because people see them.

Fantastic Four was a great film. Was it the third time the IP was launched? Yes. Do comic books get relaunched all the time? Yes. So does the same happen for comic book movies? Yes. No one was upset when Christopher Nolan was planning to put out his Dark Knight trilogy. We already got 90s Batman, why do we need more. No.

But fine, you want an original IP, Thunderbolts. Thunderbolts had never been put to screen before, excellent film.

Other multiverses:

Stephen Kings Dark Tower

the works of H P Lovecraft

Frank Baum’s (the wizard of) Oz stories

Frankenstein

Dracula

James Bond

Cheers (Fraiser, The Tortellis)

Star Trek

Star Wars

Dr Who

Warhammer 40k

Dr Seuss

GI Joe

Transformers

The Bible / The Torah / The Quran

Sure, but none of those are cinematic universes, although some are close.

Stephen Kings Dark Tower

A single standalone film.

the works of H P Lovecraft

No connected films.

Frank Baum’s (the wizard of) Oz stories

Technically with the Wicked films this kinda works, especially since “Wicked For Good” doesn’t make much sense without having seen the original Wizard of Oz. Of course this all happened well after the MCU was established.

Frankenstein Dracula

I know the “Universal Monsters” franchise exists, but I’m not aware of them crossing over much.

James Bond

Each Bond is a new start and even within a given Bond little carries over. Daniel Craig did change this up a bit by being more interconnected with direct sequels, but it’s still just a singular series of Bond films.

Cheers (Fraiser, The Tortellis)

So TV crossovers and spin-offs are where the cinematic universe starts, but with Cheers obviously not cinema.

Star Trek

90s Trek definitely has these moments within the television shows. Most films stick specifically to a single series with maybe a quick cameo, but Star Trek Generations crosses TOS with TNG, so this fits but it is just one film.

Star Wars

The original films have the prequels, so we do see the start of what will become a cinematic universe. Technically we have Droids and Ewoks… But those weren’t serious attempts. Rogue One would really start the overall cinematic universe, but that’s 2016, after The Avengers, so it was after it was established that cinematic universes can work. The Clone Wars came out in 2008, which is a direct tie in. (Also Clone Wars came out as a prequel to Revenge of the Sith.) So Star Wars dipped it’s toes with television tie is.

Dr Who

Just one film. TV series are largely stand alone from Doctor to Doctor, similar to James Bond. If there were more films this would probably fit better.

Warhammer 40k

No films AFAIK.

Dr Seuss

No connecting films AFAIK.

GI Joe

Just films with sequels.

Transformers

Mostly films called Transformers, but a few spin-offs. I think the MCU was first.

The Bible / The Torah / The Quran

Wildly different between storytellers.

Again we can debate the details, and I’m happy to, but the MCU built a world of different protagonists, and put them all together. Technically it’s just adapting the comic books, that’s what they do, but at the scale the MCU did it, they stand first.