Kind of hard to feel engaged when all you do is reverskiing as the gimbals aim for you.
Easy to throw out as a blanket statement. Those "peashooters" are completely laughed off by a Hydra and it is - with the non-engineered AX multicannon, at least - basically impossible or outright tedious to exert a Medusa by yourself(also already shows its limit at a Basilisk). If anything, most people I see still use the Guardian weaponry for Thargoid combat and it is very far from having devolved into "no-skill slugging". The entry barrier has simply been lowered by allowing the option of gimbals for newer players to it.
I say that having used both myself. So I'm not just coming out of nowhere with it. And, to go nitpicking, if you just "reverski as the gimbals aim for you" with no further input, you will quickly just get destroyed by anything other than a Cyclops(which is a pitifully easy target once you have the basics down, fixed or gimballed weapon loadout alike).
On topic - I think that the narrative reasonings for the rebalances aren't so much
absent as left for the player to make out(up?) why they occurred. EG - difficulty dropping quickly after the initial week(s) of invasion when more Titans arrived, because of Thargoids spreading out between them(I believe there was a GalNet around the time saying that exact thing or hinting at it, too). Likewise, the spires potentially* offer an insight into why the invasion kind of stalled out on the Thargoid side(not that it really was ever
that much of a threat, which might've been on purpose), and I guess why it picked up again toward the end of last year.
*I say potentially because I'm really still not sure what their purpose is supposed to be. As it is, they primarily just seem to be a tool for humans to make system cleanup around the inner core of a control sphere easier. And not in a particularly understandable way, from the lore perspective... which part of Orthrus getting slaughtered in the tens of thousands at a spire makes the hundreds of thousands - possibly exaggerated - Thargoid ships in I don't know, Eoto(back when they held it) decide to just... vanish? Similarly a point could be made to how Titans with less spires really don't seem to be off any worse than the ones with more than half a dozen. (Oya with two really just seemed to be constrained by actual target
availability, rather than
capability. And whatever the 30 panic alerts were ...)
Also reminds me how tissue sampling reigns supreme even though there's no obvious effect it has on Thargoid ships beyond inconveniencing them slightly. If instead it had a combat-boosting effect in the systems where it is used... (alongside more modest progression value, maybe)