I'm taking this Pop Cult video as a jumping off point for a very common Space Opera problem: Bad Scaling.
That's a lot of cope. It's this simple: most writers have no clue what they're talking about. Uncle George has real limits that his chosen medium imposes, reinforced further by deadlines and financial constraints, but novelists and comic authors do not.
The sort of "major fleet action" that constitutes climatic battles marking the apex of a narrative arc in Uncle George's Space Opera (and the Mouse Wars knock-offs) are skirmishes in E.E. Smith's Lensman series and Yoshiki Tanaka's Legend of the Galactic Heroes. By the time those series reach narrative peaks, we're looking at hundreds of thousands or millions of capital ships per side with tens or hundreds of millions of combatants.
That is the sort of scale that truly epic Space Opera requires, and very few authors even comprehend what that is- nevermind how it would work or what two competing forces of that size and scale would do to defeat the other. Uncle George, and others in his sphere like Battlestar Galactica (both versions), didn't even try- and George, at most, implied it was possible.
The problem is that these writers fail to see that combat--at any scale, from man-to-man all the way up to universal scale--is nothing more (in narrative terms) than a stage to develop character and advance plot. The difference is that you do so by action--what someone does and how they do it--instead of by dialog. In film or comic terms, this leads to the ideal of a scene where the entire narrative unfolds without a single word or grunt uttered; all character development, and plot advancement, occur silently.
This, by the way, is hardly impossible. Ryan vs. Dorkman did this on a lark 16 years ago, and you'll see others with experience in stunt work or fight choreography do short films like that on the regular- both to stay in practice and to add to their film reels for big boy work.
And no, Hellmouth and OldPub writers as a class don't do Git Gud so they won't put in the work required to make their Space Opera better. They rely on nepotism and corruption to get paid, just like their fellow travelers elsewhere in the Death Cult, so you're going to have to go old-school, go Indie, or go East to get your eyeballs on stuff that doesn't suck.

