Warning: SPOILERS for Legends of Tomorrow season 6's premiere.
The MCU is referenced once more in the Arrowverse, this time as a jab at The Avengers in the Legends of Tomorrow season 6 premiere. Despite being rival companies, the Arrowverse has never shied away from referencing the Marvel Universe across The CW's many DC TV shows. From characters like Hulk, Spider-Man, She-Hulk, and Howard the Duck, to the late Marvel legend Stan Lee, The CW characters are obvious fans of the rival brand. What is likely the case is that on Earth-Prime, Marvel is a comic publisher that led to the MCU being a massive franchise the way it is in the real world.
Their latest Marvel reference, however, was about the Earth's Mightiest Heroes and it came from Sara Lance. In the Legends of Tomorrow season 6 premiere, "Ground Control to Sara Lance," the episode picks up right where they left off last year as White Canary was kidnapped by aliens. While trapped on the spaceship, Sara and a captured Spartacus get into a fight with another trapped alien, with Sara doing all of the work while he stood by to watch. As Sara calls him out on it, Spartacus tries to brush it off, saying that he would avenge her if she had died. Annoyed with the not-so-undefeatable Spartacus, whose timeline doesn't have the Marvel superhero team, Sara trips him over and says that "being an Avenger is stupid," stating that a Preventer is more important than being an Avenger.
If this is Legends of Tomorrow's way to demonstrate Sara's opinions about The Avengers, it would actually fit her quite well. Ever since she boarded the Waverider, the Legends have always tried to prevent the timeline from being damaged or changed, even if sometimes they are the cause of it. To hear Sara explain to Spartacus that she rather would be a Preventer as opposed to an Avenger feels suitable for her. It almost echoes Tony Stark's "The Avengers, not The Pre-Vengers" rant to Steve Rogers in Avengers: Endgame after he is brought back to Earth.
Given Legends of Tomorrow's lighter tone, there has to be an episode at some point where the gang goes into depth about their Marvel thoughts, given how many references there have been in the past. Out of all the shows to have any cast get into a Marvel debate, Legends of Tomorrow would fit the bill the best, maybe with an appearance of The Flash's Cisco Ramon. The fact that the Arrowverse has now gone as far as mentioning The Avengers in this universe, is almost like a commentary on the unnecessary rivalry between Marvel and DC fandoms.
The next best thing would be for the MCU to start dropping some references to the DC Universe, whether it be the Arrowverse or DCEU. While this is likely not going to be the last Marvel reference the Arrowverse makes, it was still fitting for Legends of Tomorrow to be the show to mention The Avengers for the first time.