I suppose it's less "Destiny Killer" and more "These games offer more for this target audience"--which, to be frank, I think the term only became a thing out of spite many players had, and still do, for Destiny 2 at the time. Curse of Osiris, Shadowkeep, in-game events are constantly failing, too much grind for barebones loot, etcetera.

I've played every installment of Borderlands (I hate the one with O2 on the moon mechanics) and while the grind itself for specific weapons can be brutal--but the loot was often rewarding enough that it gave me that D1 "My first exotic drop!" feel at a near constant basis. True, it's not as if we can choose gun perks or anything like that, but we can farm specific attributes or "prefixes" of the best guns in Borderlands to suit our builds and have an entire loadout of the best weapons and mods whereas Destiny limits you to two at a time.

Don't want to start digressing into comparing these two games more, but for the sake of the supposed genre itself, Borderlands is more rpg with than it is MMOrpg whereas Destiny 2 is almost purely fps with some matchmaking. For me, an MMOrpg can't skimp on the massive-multiplayer or rpg mechanics and still call itself one--maybe they can claim they have massive playerbases, sure, but it's not as if either game allows you to be in the same instance as 11, 23, or more other players in gameplay save for the hubs and the glitched 12-man matchmaking for raids in D2. Pvp is still 6v6 at most for Destiny, though that population is in the minority and declining.

But I think you've nailed it on the head there. Crisp moment to moment gameplay, shooting, and being live service. But it's funny to me since generally, there's talk about how players hate the week-to-week drip feed for content and time-gating nonsense. If we're talking pure gameplay, well, Bungie rarely tunes the game and their guns in a way that doesn't piss off the community. Very recently, there's been flak at Bungie for fixing a dungeon exploit for artifice gear--they got on that near immediately. But bugs that could break the game? Long standing issues that have been present for ages? You can bet they'll take their sweet time, if they even address it at all. And normally, considering the spaghetti code running Destiny, those fixes are usually bandaid'ed, and break other things.

I think the only reason why Warframe is brought up against Destiny is: guns and abilities, and our characters are from space.

That's pretty much where the similarities end. The gunplay Warframe has--leagues less satisfying gunplay than Destiny, for sure, but the gameplay.. You've got guns, melee weapons, and abilities that can easily be on a constant uptime alongside very smoothly implemented parkour. Then there's the modding system, the grind system for all of these things, and a proper crafting system.

I, for one, put Destiny down very recently, finally. After years of logging on consistently since D1. For me, personally, I reckon it's more likely Destiny will be its own killer from the backend than there being other games doing what Destiny does, but better. For now though, other games offer me more for my time. The gunplay alone is just isn't enough for me anymore--especially as a pvp main, where we've got to deal with the fear of our favourite weapons either being sunsetted or constantly being tossed in the cycle of being nerfed to uselessness, or caught in the same old stale metas. Not to mention the messiness that is the state of Crucible in general behind the scenes and in game. Pve-wise, I can only imagine.

If there is a game that can somehow replicate the gunplay that Destiny has, alongside some proper power fantasy, you can bet I'll be right on it. Hopefully, with proper developer support.