They all strike me as providing far too little, with too awkward a buildpath, at a bad price point in comparison to seraph's. Seraph's is the only good choice, and the rest are mostly garbage. Few thoughts:
* Lost Chapter is too hard to pick up first back in comparison to a tear, and that skews things very heavily. Then add in that Luden's is 100g more for an item that isn't really that big a damage difference over Seraph's on most champions, has a worse mana pool than Seraph's effectively unlimited one, doesn't help most mids waveclear better than they already do (and in fact, the large mana pool on seraph's and the mana refund accomplishes this better, in a lot of ways)... and it strikes me more that Luden's and GLP just don't do what they need to do or were designed to do. They -aren't- good enough mana items to warrant a slot in most champion's builds.
* Seraph's already has decided drawbacks. You're putting 750 gold into an item that gives you almost zero lane presence and investing into scaling. The fact that people are doing this even on champions that WANT early presence or map pressure (and would therefore prefer to opt out of a tear), like Taliyah, indicates to me that the other items are just bad. The other items and their buildpaths just don't cover their needs in the same way old Morello did and Seraph's now does, to the point that they're willing to buy into scaling even if it's traditionally undesirable.
* Nerfing the Seraph's shield won't make people buy the other items more, because they still won't do what they're intended to do. Yes, there's a whole lot of talk now about "squishier mage builds" and "survivability with seraph's shield" as a caster color point, but that strikes me as bonus and not the root cause, since even champions that buy into Liandry's or new Morello second item -- which means they'd have the same survivability as before the itemization changes -- are buying Seraph's. Luden's doesn't offer enough, and GLP offers virtually nothing (has it even been built once in pro play?).
tl;dr: people are buying seraph's because the other items are bad, have bad buildpaths, or both; and the fact that people are consistently buying seraph's on low-synergy champions like syndra and taliyah indicates that the other items can't do their job as-is and should be changed instead.