Unfortunately, this just isn't true. Is life worth living if you're destitute and living in poverty or emotional turmoil? Won't a strong economy increase the pace at which we develop and produce life saving technologies?
At a certain point of economic ruin, I think many people will choose a strong economy over saving lives. The question is more so what the tipping point is. It seems hard to quantify and compare the total impact a strong economy has versus lives saved, but I think it's definitely worth having the conversation. Ultimately, this is a value judgment so there's no objective answer.