The series finale of Agents of S.H.I.E.L.D. had a pretty big (or technically microscopic) connection to the MCU, despite the internet not wanting to acknowledge that, but the finale would’ve actually referenced the events of Avengers: Infinity War if they had more time in the episode.
In an interview with the New York Times, Jed Whedon said they were going to mention the Snap, but it was cut due to time:
Some of the stuff they did with time travel in “Endgame” indicated that there are other timelines where other adventures are occurring. We’re following the multi-verse rule. The only way that someone survives Thanos’s snap in the movies is go into the quantum realm, and we originally did plan to give that a mention — because we used the quantum realm to move between timelines — but it got cut for time.
There was apparently about twenty minutes of additional footage that had to be cut to make the television runtime. Perhaps we’ll be able to see an extended version of the finale in the future when the series is eventually added to Disney+…