Update: Deadline offers Captain America 4 will likely follow the Anthony Mackie Captain America and be separate from the Chris Evans Captain America, as back in January, Deadline reported Chris Evans is in talks to return to the MCU to reprise the role in the MCU in some form.
So, Captain America 4 is in development at Marvel which follows the final episode of The Falcon and the Winter Soldier. The final episode reveals that Sam Wilson becomes Captain America with the shield and a new suit.
It was well done and accomplished what the writers wanted to. Sam becoming Captain America, Bucky finally got some peace from the sins of the past. John Walker was made a super soldier and becomes the US Agent. The world governments come together and find a peaceful way to deal with the displacement of half the world’s population after Avengers Endgame. Sharon Carter (descendent of Peggy Carter the early head of S.H.I.E.L.D.) is forgiven from any crimes and restored to her original place in the government.
It is the perfect setup for new stories involving Sam and Bucky. And it looks like we will see the eventual return of Steve Rogers. It is safe to say that Marvel Studios has not missed a beat in quality programming. Soon in June, we will see Loki on Disney+. Captain America 4 also has no release date as of yet.