>Yes, but backlinks don't just come from marketing, which you seem to be presuming.
I'm not presuming that. If someone finds a piece of great content via organic search on page 10,000 of the SERPS and then links it, great. That's possible and I haven't precluded the possibility. I'm saying it's incredibly unlikely and rarely happens in reality.
You are technically correct that given an infinite span of time a blogger who puts no effort into obtaining links will eventually get linked to via users who hit from page 10k of the SERPs. For our purposes as humans who have finite and short lifespans I am not satisfied giving any weight to the presupposition of an infinite timespan. So I reject your argument and state that the vast majority of first backlinks come from marketing, including stuff like telling your friends on twitter that you wrote a blog post, which is marketing.
>tons of tons of blogs get the majority of their traffic from Google with no marketing from the blog owner.
In practice this rarely if ever happens. Show me a successful blogger who doesn't submit her posts to the aggregators, linkbait from forums, share posts on Facebook, do guest blog posts on other blogs, etc. first, before there is a loyal following to do the submitting themselves.
SEO and marketing precedes organic growth, always. And probably a lot of what you're terming "organic growth" falls under the umbrella of SEO and marketing.
>Good content will wind up on sites like this or reddit and backlinks will follow.
Once blogs pick up steam this indeed becomes a thing. Before blogs pick up steam it is generally the author or a marketing agency doing the submitting, e.g. marketing.
>Google's job is to find and display good content to their users
Based on a definition of good that Google has defined in a very precise way. Have you read The Paper? G draws the conclusion from a healthy backlink profile that since other people believe the content to be good enough to link to it is probably good. Hence the disproportionate weight placed on backlink profiles in ranking algorithms vis-a-vis other factors. Backlinks in themselves are a measure of good content according to Google.
>Good content is the key ingredient, not SEO and marketing
Only insofar as if you market a turd, it won't pick up steam. SEO is nothing more than following the rules to get indexed. If you don't follow the rules, you won't get indexed, and likely won't see organic growth from search. The rules state that in order to rank higher, you need backlinks. The backlinks preclude the higher ranking and thus as a logical necessity the growth.
>Backlinks are but one of many factors involved in ranking, and their goal is finding good content, not finding the most linked content.
For Google, finding the most linked content (combined with assessment of the link profile, e.g. good vs bad neighborhoods etc.) is a means to finding good content. Google cannot assess what makes content good without assessing the backlink profile heavily, because the entire philosophy driving the SERPs is that good = linked to.