DC's Batman is a hero of few words during battle, so it's no surprise that the company would use him to lampoon the many Marvel heroes who talk too much during fights - especially when said fights leave very little room for talking in the first place. The Caped Crusader isn't usually one for witty comebacks or sarcastic quips; such actions are usually reserved for his enemies, like the Joker or the Riddler. Thus, it's wholly appropriate for DC to use a stoic hero like Batman to point out the weaknesses of talking during a fight - but this Batman isn't Bruce Wayne.
DC One Million was a 1998 company-wide crossover event that depicted the DC Universe in the 853rd century, so chosen for the time in which the members of the Justice League would receive their one millionth issue (if DC adhered to a regular publishing schedule and didn't start over with a new numbering system). In the year 85,265 A.C.E, Superman-Prime (the original Superman) is returning to Earth after spending thousands of years living inside the Sun. The people of Earth (who have since spread across the Solar System) plan a massive celebration, and the original Justice League are the guests of honor. Thus, the Justice Legion Alpha travel back in time to 1998 to meet their progenitors.
The Batman of the far future meets Bruce Wayne. The two exchange pleasantries of a sort - the future Batman reveals that in the world of DC One Million, history remembers Gotham City as a paradise - but Bruce doesn't want to accompany his successor to the 853rd century. The Future Batman responds by attacking Bruce with a flying kick, all while delivering one massive monologue. "You see you have to go and this is a martial arts move developed by a telepathic octopus species inhabiting the infoceans of Durla; the attack's telepathic as well as physical, and by the time you realize this sentence seems way too long...it'll all be over." With that, Batman is knocked unconscious.
The future Batman pointing out that the overly-long sentence seems too long is perhaps indicative of DC's feelings toward some of the more chatty Marvel heroes, namely Spider-Man. It's well-known among the Marvel fandom that Spider-Man's constant jokes during a fight are part of his character - but one wonders how he can possibly continue talking while swinging through the air and dodging attacks from enemies. By contrast, Batman is usually silent during battle, unless he's in the middle of giving orders to the Bat-Family.
Though DC One Million was released in 1998, the habit of superheroes talking too often during fights is still an ongoing issue. While the quips of Spider-Man and others certainly add character to the battles, one wonders just how fast they can talk between delivering punches. Batman, ever the stoic, doesn't often have this problem.