Severity of CV is one aspect but still remains that if vaccine is ineffective in making you immune then individual factors come into play for severity. The public data on the two 'correct' trials is too limited given the ratio of catching CV vs mortality rates. As the mortality rates currently for most countries are at worst 1/2 the level seen in their respective 1st waves (or in the UK's case less than 1/10th the first wave level) then the sample sizes are not large enough to provide statistically significant figures based on what's in the public domain.
Reporting just 5 cases of people who took the vaccine & still contracted CV is just too small a sample size to draw conculsions on the severity reduction especially at just months into the typical 12-18 month duration. That none have been serious is a great start but not a guaranteed result as the sample size increases along with the duration. With a 1% population mortality rate then you would require about 300 to test positive with zero deaths to even start to 'statistically' say it has decreased the mortality rate (vs expected 3 deaths). The introduction of using steroi_s in a similar protocol as with severe asthma attacks seems (not stats done yet that I've seen) to have decreased the initial mortality rates by up to 45% - yet has not got the positive press I would have thought that deserved nor the hope! it provides.
Understood your preparedness - but could you be that one person who becomes the equivalent to the Melbourne Hotel night manager who inadvertently led to Victoria being shut down & the Tradewinds' outbreak in Sydney etc etc. If the vaccine does not render you immune then the limiting of severity is a moot point. With the efficacy rates quoted the outcomes are infected or not - to date (I haven't seen any updates) the factual reports highlighted (from the two more reputable trials' candidates) that the level of transmission impact was not known & it would take much longer to be determined.
Whilst you are happy to take that risk - are the other four members of your family (who knows which one may not be immune) equally happy? Do you have any elderly relatives or friends etc that could be place at risk?
Then consider every other flight that is arrving in Australia that day, say 50 (2018/19 around 250 international arrival flights per day btw). Then multiply out for a week - and that suggests around 700 active CV cases arriving in the community over just one week.
In isolation, the risk to you may not seem great, but the risk at a community level is much greater. Then add in that roughly 4 out of 5 cases are asymptomatic....and regular international travel looks to be further away than anyone wants.
