I think the title of this link should be "I wanted to raise money from investors so I built an app and came up with clickbait scratch-my-own-itch startup rhetoric to get attention on HN"
I tried to log in and was told my email address had already used the service, and sure enough, a password reset had me logged in. I have no recollection of using it, so it may have been some time ago.
I like it. It doesn't quite scratch my itch, but it looks a useful tool.
I think the reactions you're getting are likely focusing on this project as a useful product or a business, not a coding exercise.
Because it's well-trod territory, with existing products that have been around for years, you're probably seeing more negativity than you would have if we all knew this was a learning project.
That said, not every step of every coder's learning process is broadly interesting to a community of people who have been programming for decades in some cases.
Usually these kinds of posts are better received when they come as a blog post about what the person's background is, what they were trying to learn, and how they felt about using those tools for the first time.