https://www.nationalgeographic.com/science/2018/11/impact-cr...
would the erosion caused by glaciers, have enough time to erase the planet-wide evidence of that hit as well?
What conditions need to be there for the erasure to work quickly?
The number one condition for fast glacial erosion is what's called "wet-based ice": if pressure and temperature at the base of the ice sheet (warmed by geothermal heat flow) is near the melting point, then ice tends to slip against the rock and erode rapidly; if it's too cold, then the ice will flow internally instead and not erode very well. Coupled climate-icesheet models so far [2] suggest it's possible to get wet-based ice even in a "hard snowball" state with limited precipitation from sublimation alone (though not under all parts of the icesheet at once).
[1] https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/JB07... [2] https://www.sciencedirect.com/science/article/pii/S0012821X0...