The Spider-Man and Captain America one interaction. Marvel Studios has made the MCU movies more connected as time goes on, as "solo" movies are now often filled with other major characters. In many cases, this has meant the MCU bringing fan-favorite characters from the comics together on the big screen and delivering fun crossovers. However, the limitations of the franchise means not every character can interact as much as Spider-Man and Iron Man, or Captain America and Black Widow.
In fact, audiences might be surprised to know that Tom Holland's Spider-Man and Chris Evans' Captain America only had one MCU interaction. The characters appeared in four of the same movies, but Team Iron Man vs Team Captain America fight. This included Spider-Man going for Cap's legs per Tony Stark's advice, but Steve ultimately got the better of the young web-slinger. Their fight concluded with Captain America complimenting Peter for his heart and finding common ground with him as a New York native. It's a great exchange, which makes their non-existent relationship going forward all the more surprising.
While Captain America did speak to Spider-Man in Avengers: Infinity War and getting dusted, there wasn't any room for more crossover.
Spider-Man and Captain America's MCU interactions being so limited is certainly a disappointing result of the shared universe's storytelling. While the lone interaction didn't seem destined to ever happen for years, Captain America: Civil War teased a chance for their great comic dynamic to play out more on the big screen. Instead, Spider-Man and Captain America's MCU stories went in opposite directions. Although the MCU is filled with missed character crossover opportunities, not giving two of Marvel's biggest heroes more than one scene together is certainly not what audiences would've expected.
Of course, there is a chance that Spider-Man and Captain America had more MCU interactions off-screen. They were both present for Tony Stark's funeral, for instance, and it is somewhat difficult to believe that Steve wouldn't go talk to Peter after this devastating loss. While Peter could still interact with old Steve Rogers potentially after Avengers: Endgame, Spider-Man's best chance for more Spider-Man 4, or both of them on the next Avengers team.
