The scribble stick figure art is funny. The fisherman in sunglasses on the little wooden boat and the big green fish on the title screen have a proper notebook doodle charm. The HUD is informative in the right way too: Depth 167m/800m, Line, Reach 100m, and the vertical depth bar on the right showing where you are. You really feel the descent toward 800m. Having a shop and a target system suggests a real progression loop rather than random fishing, and controlling everything with mouse movement (holding to reel up) is a good relaxing choice.
My problem: I spent a long time diving and my money stayed at $0. It never became clear HOW you catch a fish. I passed the hook over plenty of them and nothing happened. A "hooked!" feedback or a visible catch area on the hook would fix that immediately. The panel also said "No target" the whole time and I never figured out how to pick one.
One more thing worth checking: around 344m some untextured blue, orange and green rectangles appeared in the middle of the screen. They look like placeholders that made it into the build.
The skeleton is there (depth, shop, progression). It just needs to communicate the core mechanic.