Help! My SEO has always suffered because of bad DA and no backlinks

I create side projects often, basically one every year probably. I buy never seen before - but nice and catchy domain names which have zero da and basically were never mentioned before in the history of the internet - so no backlinks.

I have found that with this practice, google has a very hard time indexing my pages/blog even for the keywords I'm targetting let alone to actually compete for something in the first page. I'm a senior web developer and I've followed the google seo documentation in detail and even added valid and logical structured data to all my pages.

Now I'm actually more serious with a side project which has started to turn a profit, and I'm creating a blog for it. But it is in the same position - zero backlinks, da is basically non existent. My blog for this side project will be long term, my quick term visitors will come from sharing the articles in social media and reddit - but the long term is supposed to be SEO.

Do you guys have any suggestion to get rid of this bad DA and zero backlinks curse? What should I do so google takes my things more seriously?