Do I think that this niche of the porn industry, aka Erotic/Adult Visual Novels and Games, is over saturated? I have an answer but it's sort of complex:
There are certain themes/tropes that are very over used... Things like the slow build up that always starts with peeping, creeping around the house at night, walking into bedrooms without knocking, the broken bathroom lock, perving on women as they sleep, and the list goes on... These sorts of things are used very highly in lower to medium quality VN/Games, usually by newer developers, who have very little experience and/or talent for making these things... Most likely because they were seen in other VN/Games, and are easier to start off with in the slower corruption/seduction/mind control build up grinders and visual novels... I don't think it's too bad, when just a couple of them are used, but over the years I've seen a huge number of VN/Games that pretty much use all of them, in one form or another... And therefore the market it over saturated with these copy cat type starters... It just depends on how quickly or how many are used, and in what context, when determining if they feel out of place and/or unoriginal, some of the time...
The Erotic/Adult VN/Game market is also a bit oversaturated with the Incest theme (I'm sure the pro-incest folks will spout out at the mouth in defense of this one)… It's not as bad as it was a couple years ago, but it is still very present... And not because it's necessarily desired, by the over all readership/playerbase, but because newer developers believe it's an easy money maker... This misconception is mostly due to the incest gold rush, brought on several years ago by a tiny handful of big money makers, around the same time that Patreon was gaining popularity amongst developers in this market... An insane number of newer developers flooded the market with Incest themed VN/Games around that time, and it really hasn't slowed down at all... It's not really popular amongst the greater readership/playerbase, but instead is popular amongst developers... Thereby giving the impression that because there are so many VN/Games using it, it must be popular overall... It's a misconception...
Which brings me to the direct question being asked... Is the Erotic/Adult Visual Novel and Game niche of the porn industry being saturated? In some ways, yes... If you look at what has happened in the past, coupled with what is still going on, there are so many newer developers beginning new projects... But that was also true in the past, around the same time as the gold rush I mentioned... And if you look at what has happened before, many of the new starters eventually abandoned their projects... Several factors made that happen, but the primary one was most likely the difficulty of making a unique and well designed VN/Game... It is not something any joe off the street can just begin doing, and expect it to be all that easy and/or do well... Once the market gets it's first taste of a new product, it is touch and go, as to whether it will be accepted well by the majority, or hated, or just sort of chug along... There will always be some who like a new project initially, but will it be good enough to last, and/or will the developer stick it out? In a lot of cases, they will not, based on the patterns of the past... But for those deciding to stick it out, the quality can still vary, depending on what they are trying to accomplish in the first place, and how they actually do over the long haul... Some find their small niche of this niche market, get some paying fans, and they are satisfied with just that... No desire to be this huge big hitter... Some continue on, with very few paying fans, because their product just isn't appealing enough, and/or isn't really all that good, but they keep on trucking regardless...
Because there are so many newer developers of varying skill, experience, talent, etc... The market is flooded with varying levels of quality and quantity... In the western market, it is primarily made up of Amateur developers... It's mostly the Japanese market that is full of professional business made products... And in a mostly amateur market you have various reasons why people make these things... Some have ideas popping in their heads, and want to put their ideas into their own version of a VN/Game, with money being an after thought... Some have ideas, and have the skill/talent to make these things, so they do so, with money only being a means to an end... Some want to go pro in this field or others, and this market is just a stepping off point for achieving that goal... Some believe they have talent and therefore they try their hand at this market, due to large ego's, but it ends up they don't... Some need to feel a sense of belonging, regardless if they have the skill/talent, and their over all goal is recognition/prestige, needing their ego to be stroked (consciously or subconsciously)... Of course, there are lots of other varying reasons... But a majority want to make money as their true end game, even if they enjoy making these things or not... Hence we have a market saturated with newer developers alongside the more experienced developers... And it's a gamble for both the developers and the readers/players...
You also see the market flooded with developers who want to milk a project for as long as they can, while pandering to their paying fans wishes, again in order to prolong it's existence... Because with Patreon being a subscription based system, the longer you can hold on to those subscriptions, the longer you keep making money... Why finish a project too quickly, because that would mean the flow of money slowing down and/or stopping... Then he/she would have to come up with a new idea for a new project, and that is harder (and more time consuming) then just stringing the current project along... Pandering so as not to lose current subs, teasing some new content now and then to keep folks satisfied, and maybe bringing in new subs as new people discover the project and come on board, over the long haul... I would hope this isn't the norm, but sometimes it's hard to know/tell...
Sorry for the long winded answer...
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