This is a somewhat controversial game, but it was only able to achieve that controversy by being popular in the first place.
The author had an earlier 3-part series called Heroes Rise, that focuses on a superhero getting powers, beating their first enemy, going on a reality show, then becoming an influence on the whole nation.
This game is a side story with a new protagonist, a hero with a very clever power: you are an animal/human hybrid, but the animal you're mixed with changes every day.
The focus of this game is different from the earlier series. Your character is a representative of several persecuted minority groups (the animal hybrids, those with uncontrollable powers, and another one I can't remember). The main themes of the game revolve around the treatment of these minority groups. Also, your sister's powers are killing her, and a mysterious benefactor has offered to cure her in return for several unnamed favours, to be collected.
The focus on the minority groups has led to a lot of reviews and forum posts describing the game as having 'too much politics', which is usually a dogwhistle for alt-right people who don't like LGBT representation (which exists in this game; there are trans and non-binary main characters).
However, I feel like there are some issues here, but not with the content itself, rather how it's presented. The first Heroes Rise games were all about action, but this game is largely about reaction. Instead of picking what you do, frequently you're told what you or others do and then given the choice of how you feel about it. Quite frequently choices are forced on you, and you can go several pages without a choice, more often than the earlier games.
I believe that if the game had been rewritten to feature more action and choice that the number of negative reviews would have gone down a lot (except for virulently anti-LGBT people), because a well-written game can handle all sorts of diverse politics. For instance, the Heart of the House prominently features a nonbinary main NPC with non-standard pronouns, but you see a lot fewer negative comments about it.
The Sea Eternal had a similar issue, I believe, where you were frequently told what you were doing and what you thought, and I think that it just doesn't make for an enjoyable game experience. And I think it's possible to have games with strong pro-LGBT messages that give you freedom of action and feeling: Howling Dogs, Birdland, With Those We Love Alive, and Tally Ho come to mind.
Another thing that may have dinged this game's popularity (although it's still a very popular game, just not as much as the other games by this author) is having forced failures. There are situations in the game where you have to pick between 2 very bad outcomes, and Choicescript games that do that tend to suffer.
However, I've noticed that those same ingredients that are drawbacks as games (reduced interactivity and forced failures) can also help make your overall story better. It's no coincidence that the Nebula writing award nominated games tend to sell poorly: they all tend to have tight, railroaded stories with lots of failures to build up a big character arc.
Anyway, I did like the overall story of this game, I'm glad I played it, and I look forward to the next game and the eventual crossover with the author's other series.