I don’t believe that’s true. ABC’s Agents of SHIELD, Daredevil, Jessica Jones, Luke Cage, Iron Fist and The Defenders are all part of the MCU even though they haven’t appeared in movies yet. All those shows make reference to events that happened in the MCU movies. Don’t believe me, ask Kevin Feige.
Tv-movies
Kevin Feige and the guy over the TV shows don’t like each other, so it’s pretty much a one-way street. The shows make some reference to the movies (probably Disney ordering it for free advertising), but the days of the movies referencing the shows are pretty much over. You won’t be seeing any of those Netflix heroes in the MCU movies, though Daredevil would make sense in Spider-Man.