Really don't agree there. Buck's pretty much the same character in both games. He's hardly the comic relief of Osiris - he might have a wisecrack or two, but that's it.
There was more there than that, out of focus and more subtextual: Buck questioning whether it was a good decision to join the Spartan-IV program, being used as the guinea pig for Locke's armor locking device, not getting as many "omgsocool" cutscene moments as other members of Fireteam Osiris, and the like. The totality of the portrayal being, Buck's a poor fit for...well to be frank, animu bullshit team.
Personally, I think making Buck (and all of Alpha-Nine bar Dare) Spartan-IVs was silly, but again, another issue...Locke and Osiris are symbolic of the Spartan-IVs replacing the Spartan-IIs, but that's a theme that neither H4 or H5 are really interested in exploring.
That was a huge chunk of the problem. Humanity uplifting itself to its prehistoric glory has been the thematic elephant in the room for the supposed "Reclaimer trilogy". Halo 4 introduced the theme well enough, bringing back plot seeds that were planted as far back as Halo: CE, but Halo 5 really dropped the ball in how it waffled about representing Spartan-IV's.
Had they done something like UNSC and ONI deciding to decommission the ODST program, and giving active-duty ODST's a choice of joining the Spartan-IV program, folding back into regular service, or early discharge, it would have reinforced that theme of humanity being in a period of rapid, seismic advancement.
Then Buck's characterization would have been more sensible, representing skepticism towards humanity's advancement, forcing the player to consider what of those left behind, and leaving the player to question what of humanity will be discarded to make these massive technological, societal, and cultural leaps.
And he would have have a definite niche within Fireteam Osiris, representing the team's conscience and sense of morality in the face of superhuman augmentation and equipment.
Which sadly, because 343 seems to want to get "back to form" with Infinite, it seems this incredibly fertile ground for compelling storytelling entirely consistent with past games --
including Halo 5 -- is just going to be left behind. Done right, it would have retroactively made Halo 5 a
better game than it was, giving it an effective place in Halo canon.
Maybe, but that doesn't change how John becomes more of a character from H1 to H3, at least in as much that he gets more lines per game, and his motivations tend to become more personal. Don't care about Johnson or Cortana? Don't think John should become friends with the sangheili who glassed Reach? Well, tough. Whatever gripes I might have with 343, as far as characterizing John goes, they're continuing the trend that Bungie started.
Which came first, the chicken or the egg?
Did players cotton to John-117's characterization in the second or third games because Bungie wrote him congruent with players' expectations, or did they spend their time subtly and intentionally crafting player expectations to set up story beats in later games? Or more to the point, John-117 is still as much a self-insert in Halo 5 as he was in Halo: CE -- because the writers, frankly, manipulated players over the course of several games into having the same opinions and reactions John-117 would in game.
Del Rio's a weird case, and IMO, you're giving the writers too much credit.
I'm not giving 343's writers credit for anything -- I'm pointing out how badly they dropped the ball on that.
...because the UNSC apparently agrees he's an asshole, because Lasky's been put in charge of Infinity by the time that John and the Didact reach Earth.
Yeah, that in particular is a story beat that makes no damn sense, Del Rio made the right call. Players only accept it because Del Rio is the designated asshole, John-117 is the designated hero, Cortana is the designated damsel, and it's cathartic to see Del Rio "get what's coming to him" for defying the designated hero.
Halo fans love to compare that to Cutter's badass speech of badassitude in Halo Wars 2, saying shit like "that's how a
real UNSC captain handles adversity, stand and fight rah rah!". Completely --
somehow -- missing the point
Spirit of Fire nuked its own slipspace drive, was down its
military AI and had to make do with a civvie logistics AI, and was critically low on (severely outdated) manpower and materiel. Cutter had no choice but to commit himself and his assets to a suicide mission, had to distract his subordinates from that it was a suicide mission, and had to boost morale while getting them on the task of maximizing their odds of survival, let alone victory. Especially after Isabel's dumb ass just blabbed an otherwise spot-on appraisal of the tactical situation to the entire fucking command deck.
"How a real UNSC captain handles adversity"...yeah, just not in the way most Halo fans noticed.
Because it was probably the best-written, blocked, framed, and animated scene in the entire game series to date. The subtext of that scene is incredibly important -- the cuts to the command crew showing the impact Isabel's dialogue is having on them; Jerome-092's body language shifting to "
shut the fuck up" mode; Cutter looking around to assess how much damage Isabel just did; Isabel's facial expression shifting from openly and angrily defiant, to embarrassed and humbled, as she figures out Cutter's damn well aware of the situation and is covering for her massive morale-killing fuck-up; Cutter and Jerome-092 sharing a look and nod because they know what's up and their only hope is to fully commit.