Flu....
...has nowhere near a 3% death rate. Neither does COVID-19. The actual number of infections will be a lot higher than the number of cases so dividing the number of deaths by the number of cases (aka the crude CFR) will always overestimate the death rate except very early on in the epidemic before people have had chance to die of it. The infection fatality rate is the important number, that's your overall risk of dying if you get infected although it doesn't account for age and, as you correctly stated, this kills the same people that seasonal flu does.
The WHO report from mid-February estimates the IFR at 0.3% - 1% : https://www.who.int/docs/default-source/coronaviruse/situation-reports/20200219-sitrep-30-covid-19.pdf?sfvrsn=3346b04f_2
A report based on data from the Diamond Petri Dish cruise ship puts the IFR at 0.91% - 1.2% overall depending on sampling and 7.3% - 9% for the elderly, who are the main clientele of cruise ships : https://cmmid.github.io/topics/covid19/severity/diamond_cruise_cfr_estimates.html
As for flu, well: https://wwwnc.cdc.gov/eid/article/19/1/12-0124-techapp1.pdf
The global CFR for swine flu was 0.048% across all ages so the IFR will have been lower than that, possibly less than half. The Asian flu pandemic of 1957 had a CFR of 0.3% which is the bottom end of the current IFR estimate. The only flu pandemic that has this beaten on paper right now is the 1918 one but that had more severe economic/social effects as it killed the exact opposite of the people who are vulnerable to COVID-19.
My guess is that the IFR number will go down as data comes in from countries that don't have China's spectacularly bad air quality.
There is another side to this; although less than 1% are dying of this, it's still putting a lot of working-age people out of action for a few weeks which won't play well with the just-in-time distribution model that everything is built around in the West. That's why slowing the progress of the pandemic is important, so as to minimise the proportion of the population who are sick at any given time. It also put about 5% of cases in China in the ICU which is a burden that the NHS is ill-equipped to bear, now that it's been organised so that all resources are fully utilised by not having enough of them.