Why do light novels and manga have long titles? So, I came across these comments in an r/manga post:

KibaTeo: Even a short series became an isekai
MonochromeGuy: That statement itself just sounds like a LN title.
in0ri: Gotta triple the length of the title, bro
Irru: Even Though This Was Supposed To Be A Generic Romantic Comedy, I Somehow Got Transported To A Different World!
KibaTeo: . . . is that an actual series tho? cause it sounds way too plausible
CelioHogane: He just tripled the lenght as it was asked.


I was wondering... why is this a thing, though? It seems that lots of series these days (especially light novels) are given very long and descriptive titles. Some classic examples include:

Oreimo

short for: Ore no Imouto ga Konnani Kawaii Wake ga Nai
translation: My Little Sister Can't Be This Cute


Watamote

short for: Watashi ga Motenai no wa Dou Kangaetemo Omaera ga Warui!
translation: No Matter How I Look at It, It's You Guys' Fault I'm Not Popular!



And here's a more recent series (that doesn't seem to have a shortened nickname yet):

Imamade Ichido mo Onnaatsukai sareta Koto ga Nai Onna Kishi wo Onnaatsukai suru Manga

translation: A Story About Treating a Female Knight, Who Has Never Been Treated as a Woman, as a Woman



One would think that having super long titles would be a disadvantage because they'd be difficult to remember :P So, my question is, why is this style of title so common? Is this a recent thing? How did this trend of super long titles come about?
The Anime Man explains this in his video.

TL;DR:


People get lazy to read the blurb of the novel (the short summary usually at the back of the book) to know what it's about, so a longer title will be more descriptive than titles like "Wish".
The LN industry is getting bigger, therefore everyone will eventually run out of titles to use (even movies there are some that have the same title which is not good), a longer title will make your LN unique and stand-out. Top selling LN in the first half of 2019 according to Oricon.