No. Expensive equipment produces excellent images in experienced hands, and it is not a requirement for good Antarctica photography. Antarctica is naturally dramatic, with bright ice, reflective water, unusual light and wildlife that is often much closer than people expect. Someone who knows how to use their phone quickly will frequently come home with more meaningful photographs than someone struggling with a new professional camera.
A dedicated camera earns its place when you already understand focus modes, shutter speed, exposure, lens choice and file management. If you don't, buying thousands of pounds of gear a month before departure won't fix that, and it may actively cost you photographs while you search through menus.
Skills, familiarity, timing, patience and observation matter more than the price of the equipment. That's not reassurance, it's what actually happens on the ship.
If you want to improve your photography before the trip, the highest-value thing you can do is practise with what you already own.