I agree it will be but I disagree in that I think it is today too, sure infections are important but they’re only ever testing a fraction of the population and deaths tend to give us an accurate reading nationwide.I think judging deaths will be the best way of measuring success or failure at the end of pandemic, whenever that may be. In the meantime, as for the day to day - the rate of infection should be and will be the factor behind any decisions such as social distancing, quarantine, shielding etc.
It’s like the difference between running an opinion poll and the actual general election.
Polls are often completely wide of the mark as luck on who you get comes down to it and they often don’t represent the whole country.