A few thoughts:
Holding up a single title (Halo) as a counter to the shopping list of narrative based titles on PlayStation is in itself an unbalanced comparison to draw~ it's also a bit awkward because as popular as halo has been for multiple xBox generations, it's rarely held up by third parties (as far as i can remember, which could be flawed) as a leader amongst the pantheon of great videogame storylines, across platforms~
The OP is right, xBox could use more iconic franchises.
But, you know, i don't think we need to have an unwritten rule that says serious consoles need the same game library touchstones as PlayStation. Nintendo has a different model, whereby the franchise and its touchstone features are the selling point, rather than the individual games' characteristics~ xBox could well just be a console for carting around, chucking on TVs and playing multiplayer with friends on.
Or some other non-PS inspired approach.
There's no rule that says the narrative-centric PlayStation is the only format that works for top of the range hardware oriented consoles.
That said, as an individual buyer, I'm more interested in the depth and ambition of PS titles.
What's the point in xBox having such brain bending power if all they're gonna put through it is CoD and Fifa and whathaveyou? CoD is hella optimised for smooth online play, it is never going to be a resource hog. They need some big sexy exclusive title that makes the unreal demo look like it was built for an inferior console.
I can imagine an article 10 years from now, looking back on another underwhelming xBox generation, saying: "while xBox delivered the most powerful conole ever, they never really produced many games that took enough advantage of that power to convince neutrals to buy their console over the more popular PlayStation brand"
Surely game developers won't design something that requires more than the PS5 to run? They would alienate well over half of their audience~ not only might the PS5 simply work better than the series x (uncertain), it would also force non-exclusive titles to make sure they run on the more popular console, first - making, on some level, even non-exclusive titles PS-centric~
The above is heavy on speculation, and I'm not prepared to fight to the death to defend any inaccuracies or big jumps of assumption i may have included. Might be happy to exchange a few civil words~