Want to hear the truth ?
Go read more chinese and jp novels, and study the current state of nowadays readers
Switch your cover first
Internet is now a mess unlike years ago. Most people grew up and internet is full of "zoomers", often them having a poor IQ.
IRL not sure if you know, teenagers now all accept animes unlike before "it is for degenerates", look at "shipcore" with the anime cover, it is on main page in rankings. [EDIT : Shipcore is a great series and with a great cover. I am a anime-lover myself and i am not bashing anime culture]
Reasoning analogy : Why would a teen be attracted to a cover of a random spaceship when 1) not interested in space 2) nothing special to the spaceship when other novel have a spaceships with big GUNS exploding an enemy ? 3) a gorgeous girl is better than a spaceship, because most readers are males AND even women prefer talking a beautiful woman compared to a unattractive man
Next, write a very interesting summary, the kind of eye-catching
Related to first point, readers now have too much FREE CONTENT available. Before there was just a few games, and dozens of mangas or novels. But NOW ? You got hundreds of free games OR paid games where you can......... , mangas = you dont even have enough time to finish the long list that accumulate, and novels, oh boi, english ones are enough to make you busy, but you take into account the chinese/jp ones than you are busy for years, BUT THEN it's even crazier because people now read MTL (machine translation) and go to the raws with THOUSANDS of novels full of THOUSAND CHAPTERS
One of my chinese favorite author said :
[[[Now readers are bad quality. They drop any series for any small reason. Also you can't even write a not handsome MC anymore or FL not being gorgeous. The old masterpieces are lucky, bc if they appeared nowadays they would flop easily. Especially some specific ones. Because green-hate/rape is a big taboo now.]]]
Title
Now it's mainstream to write the title AND/or summary with spoilers
Just like for cover, people don't have time to guess your plot and your mysterious summary.
AND they got HUNDREDS of novels to pick in the list. AND they surf far too fast on internet to pay attention to non-eyecatching things
Now authors beside already-famous ones don't use "poetic" titles/summary
Analogy : Which is more attractive for a teen : "The wind is surging" OR "I learned to manipulate wind and became the most mysterious assassin"
Third : thriller, serious-english plot, is "hasbeen"
Now it's more about coolness, epicness, comedy, vanilla, romance, etc
Before there was NTR-boom in doujins but now it's vanilla-boom. Also if you check, lot of novels prefer the "mc is op easily" compared to "grow slowly". Not that it started the genre, but Onepunch-man basically explain that OPness is attractive.
Readers have not enough time to wait for the MC doing 3 full arcs of plot where he finally get his full gear.
and anime-culture is far too popular globally
See old animes doing cliche of otaku-guy is alone in corner and hiding hobby ? Now the whole jp class probably watch animes (but still lot of douches)
Also you know Warhammer IP ? If we ignore the recent very popular trailer of a new Warhammer game, how many fans do you think like it vs the ones that like animes ?
And gears of war ? If you give choice of picking Gears of War vs Zelda breath of the wild, to all teens in the world, which would win in your oppinion ? Not that it's not attractive, but anime-culture invaded everywhere.
TIME. People's time is limited and unlike before, time is even more precious
Now people got smartphone. Even the time in the toilet or waiting in the bus, can be occupied with entertainment.
Also unlike before, TIME is precious. For 5min, people could do a quick game, or read a fast-food novel where MC killed hundreds a double-hand sword, or explode battleships at the dozen. In 20min, they could have watched dozens of videos that are funny.
LoL big long matches are now less popular compared to URF, because they are freaking too long.
TikTok showed the road of "condensed time". If you look at some youtube videos, they get far less views and comments compared to the version posted on YOUTUBE-SHORTS. Heck, lot people like watching "nutshell/recap" and not whole movies.
Even jp authors now do popular "1 page = 2 images" mini-mangas on twitter
Now forums are far less populated, especially bc of "discord" app. And most zoomers (and coomers) hate long paragraphs.
Last : now people want relaxation or excitement
Smut is far more popular vs SFW. Teens are a bunch of hormones. Even girls. Reddit is proof.
Also it's why "fast-food" novels are more popular. Why care of a no-powers dude that go a haunted mansion and searching, when you could use this time to read a necromancer MC use an unkillable zombie army to destroy a city.
But there are also the older audience that want to MC living slowly in the countryside or inventing stuff or dating sweetly peacefully
Now shitty love-triangle romance lose in popularity compared to MC-FL dating or married from ch1.
And the very dumb MCs appear less often
If before people wrote their novels far more seriously, now it's more about catching popularity, even if they must not write what they like.
If before there was Mushoku tensei (the anime only now but novel is the ancestor of isekai-trend) with quality, now you see dozens of
If you check pixiv, most freelance jp artists focus on popular theme or the anime currently popular in the season (spy x family for example or genshin)
Also english novels are far less attractive than all existing jp/chinese/KR novels
AND scribblehub is just one among many english websites