Yes and no. Yes, mortality is low generally, but grows exponentially with age, so pretty high for older people (1-10+ %).
And you don't have to choose death as your trial end point, you can take something else that is clinically meaningful, e.g. duration of stay in the hospital (not an expert).
What seems to make things difficult with Covid (according to a German virologist working on treatment options) is that we more and more believe Covid is a conglomerate of several different "sub-diseases" (can't remember the correct medical term), i.e. the virus can trigger qualitatively different physiological reactions in different people, and it's not clear at all why.