As I understand it, Owen K.C. Stephens was involved in the design work for the Star Wars Saga Edition ruleset. One of the design decisions in that system is that attack damage (and AC!) scales by character level, in addition to damage provided by the weapon and any other feats or talents. This design choice, I have heard it argued, is setting-appropriate because Star Wars has never been about min-maxing equipment. Characters in the setting are typically seen going about their business without fussing over min-maxing weaponry or equipment. Han doesn't "upgrade" his blaster pistol over the course of the series. Hell, most of the characters don't even wear armor.
In Pathfinder, as well, a longsword is a longsword (not a "rusty longsword" or an "azimuth longsword") and the gear race involves accruing magical versions of the longsword or other pieces of equipment that let you accomplish things beyond the limits of mundane equipment, ie something other than just straight damage. This is also, arguably, setting appropriate. Magic stuff is powerful. Magic stuff is not easily manufactured. Some of it comes from a distant age of legends and can't even be made anymore. Magic stuff is worth fighting over and spending outrageous sums of money for.
Have there ever been any design or setting reasons advanced for why Starfinder has structured its weapon tiering system the way it is? Why does the highest tier laser pistol do more than 8 times the damage of the first tier pistol? Why are these items so rare that finding them is tied to your character level and not to the settlement level in which you are searching?
What is it about the Starfinder setting that makes this design choice appropriate? Are there other d20 rpg systems that tie weapon damage so tightly to the tier level of the weapon, as opposed to the various feats and traits picked up over levels?
I think I understand the mechanical reasons underpinning the design choice, in the same way I can understand why Mass Effect 1 had me grind through progressive tiers of what was functionally the same weapon in an effort to balance encounters and give me something to spend my otherwise worthless money on. I guess I just feel less inclined to ignore the world-building ramifications of such a design choice in an P&P RPG than in a video game...
Can't talk about game design, but I know that I quite enjoy rolling more than 8 dice by level 20. I feel I've earned it. At level 1 it wouldn't be as satisfying.
It really depends on how your sci fi works. All games are different. Setting up a house rule that lets the player treat their weapon as any one weapon with an item level equal to or lower than their character level is really easy, and now that I think about it, an amazing idea.
So are you pro or con?
More confused than anything else, really. Probably shading towards con, but looking for a different perspective. Starfinder is different from what I was expecting, which was something hewing closer to the Pathfinder and Saga branches of the D&D tree. While I expected some 4E shifts with respect to class resource allocation (hell, Saga has been praised/accused for straddling the 3.5/4 gap in some of its design decisions), the calculated, mathematical arch of the weapon damage table wasn't something I expected.
I can potentially see it in SF we have kind of double hitpoints. But we also have less full attacks (potentially) compared to PF. so if you hit less, and have to face higher hitpoints, the way to compensate is to have higher punch guns.
If we used PF model weapons, you'd be subtracting the weapon specialization bonus of SF, and your +5 sword isn't doing that much more dmg than a +1 version, even with buffs. So if we kept the double hp, but also lower number of attacks of SF, it'd take a bit longer to bring down a target.
I suppose an alternate approach would be 'same base damage' but different grades of the same gun allows a different mechanic in applying things like weapon specialization bonus. Like a high level guy using a lowbie version of his pistol can't apply his full bonus (because reasons) but a high level guy (or even a low level guy) using a top tier gun gets a higher multiplier on his bonus. But High level guy still does more dmg than low level guy using the same high tier gun, etc.