That's a tough one to be honest. There are good and bad about both. I like being close to family, and if anything that's the hardest part since Australia is so far away. This pandemic took a toll, mentally, physically, and emotionally with the lockdowns.
Minimum wage is higher here. Cost of living however is higher here than many US states (perhaps not all, but many US states it is cheaper to live depending on what city/town and OPs profession.)
Healthcare, in the US it's an arm and a leg cost for treatment. Here, I think it's more affordable, but it has its caveats in terms of wait times, referrals, etc.. in a healthcare system that is already struggling, not funded enough, nurses are protesting over the poor pay or leaving the profession, lack of safe patient ratios depending on the state.
In terms of food, the food at the stores are healthier/less chemicals I've noticed. People here try to adopt healthier lifestyles, it's great getting into it. I do miss food and the variety in the US, I must admit there is less option and variety compared to US grocery stores. The restaurants here are great, less chains and more mom and pop shops with authentic foods. Great coffee here.
I get that everywhere there is a housing issue due to inflation and other issues, but no joke seriously it's very very bad here in Australia. Worst than the US in my opinion. Even when the US in 2008 had that bad recession, there was not as bad of blowback here. Houses and rent have only increased. Covid exacerbated this problem even more. You get way less bang for your buck here in terms of housing. It's so expensive, even for the wages received here. (Again this may not apply to everyone but just my observations). So when deciding to immigrate permanently please just consider this in mind. Perhaps even come for a visit before making this life decision as it's a big move, it's far, and it'll be expensive.
I love the USA, it's imperfect, and there are many things I don't like about it. However, Australia has many issues as well, some that aren't as openly discussed and you don't find out until you're actually here. No country is perfect unfortunately. It's a hard decision, but for me personally I spend my time between both. I wish you best of luck, and you know what is best for you OP.