Developing visual novels is not as expensive or time consuming as you think, otherwise ORCSOFT and Miel would be out of business. And at least those companies have the decency of putting voice acting in all of their games, and ORCSOFT in particular has a quality of art that DarkCookie could only dream of being half as good.
One of ORCSOFT's titles was also fairly long, 17 hours of read time. And that's a VN with no gameplay, just story and sex scenes. There's also titles like Black Lilith's Taimanin Yukikaze 2, with a read time of 26 hours. Summertime Saga is estimated to have around 28 hours of play time as of v0.20.14] by the way.
You could say Summertime Saga having both gameplay and story on top of tons of sexual content makes it harder to develop, but VN's like Sengoku Rance have all three of those at higher quality than SS and it even has 60 hours of playtime.
Then you could say those are big companies with entire teams and big budgets behind them, but here's the issue; DC as a single person is bringing in as much money as some of the best selling visual novels of all time. The entire Rance series, comprising of 16 games have in total only sold like 1 million copies across a time span of 34 years.
Meanwhile DC has been earning at least 50K$ a month since November of 2018, once even hitting a peak of 80K$ in October of 2021. That's around 3 million dollars even after the cut that Patreon gets.
To put this into perspective, of the 30 or so best selling visual novels of all time (there being 40K visual novels in VNDB alone), the lowest of them, Dies Irae, has only sold 100K copies, at 40$ for the whole thing it amounts to 4 million dollars. The game has a fantastic story (or so I'm told), a read time of 80 hours, voice acting, sexual content and pretty decent art in my opinion.
Obviously that sheer amount of money didn't go all to a single person, not to mention the VN was originally released in 2007. So in short, Summertime Saga's development has no excuse no matter from what angle you look at it.
