While Marvel has literally thousands of characters they can pull from to be part of the MCU, Paramount Pictures has an entire toybox to play around with. Paramount has already made billions thanks to their Transformers franchise, and now they're looking to team with Hasbro on an entire cinematic universe made up of five toy and cartoon properties.
According to THR, Paramount and Hasbro are building an interconnected world that will consist of G.I. Joe, which has already had two big screen efforts; plus Micronauts, M.A.S.K., ROM, and Visionaries. Just as Akiva Goldsman was able to expand the Transformers universe, a new writer's room will be put together to build storylines for properties that many people have never heard of.
At this point it's unclear if these movies will cross over into Transformers or remain separate from Paramount's top franchise. G.I. Joe and Micronauts are probably the most popular of the bunch, but there's a lot of love out there for M.A.S.K., which stands for Mobile Armored Strike Kommand. The toyline consisted of vehicles that could convert into other armored vehicles, and centered on a heroic strike force battling the villainous organization, V.E.N.O.M. ROM was most popular as a Marvel comic about a human who joined the interplanetary spaceknights. Visionaries was a failed line of action figures about magicians with holograms on their chests.
For the record, M.A.S.K. was my favorite toy line as a kid next to Transformers. The cartoon was great, too, although it only lasted a single season.
So if you're tired of everything being turned into a giant interconnected universe, blame Marvel.