Nhhhh it's a bullet hell game with loot, and it doesn't drop interesting crazy loot, and it doesn't look unique. That's the problem right there (I mean bullet hell and no interesting unique look and loot) ... if you click on the tags within steam itself, you will see why.
So why you ask anyway, despite me just telling you to look that up yourself ;P
Rabi-Rabi -
http://store.steampowered.com/app/400910/ (This is a big one)
Space Moth DX -
http://store.steampowered.com/app/425340/Starward Rogue <--
Close Order -
http://store.steampowered.com/app/383800/ The Bug Butcher -
http://store.steampowered.com/app/350740/ (another big one)
Endica 4 the Dream King -
http://store.steampowered.com/app/343150/ Sora -
http://store.steampowered.com/app/390730/ (Something SHMUP fans especially know about, but very niche)
So lots of bla bla and text and links... I just wanted to show that chronologically, SR released right between 2 big SHMUP / Bullet Hell releases one of which even I (someone that hates bullet hell) would want to play at some point (That's Bug Butcher obviously ,p). Look at the sales of the games I listed above on steamspy and you see...
Shadow Rogue.. ..
Stalwart Rogue.. Starward Rogue fits right in the middle sales wise. (Btw, that was a joke on the naming.. don't just type Rogue, you never find this game in steam :p)
Also for the record Bug Butcher steam discussion has a very Interesting topic about Spanish translations in case you ever thought translation work was as simple as translating words ,p
Point being: Genre flooded in January, very unusual to see that many games in the same genre (kind of) And tons of other games I didn't even list released, the week SR released especially.. so lots of contenders, huge swath of other games. Market flooded, literally. Still not even half way through my discovery queue for LAST month. ^^