I agree that distribution and marketing is incredibly important.
However, self publishing being ‘close to free’ isn’t really accurate, depending on your goals.
If you’re intending to publish as a career building move, you want as professional a novel as possible, then there are several expenses involved: cover art (ensuring that there’s no AI involved, MAJOR backlash on that), developmental editing, line editing, and formatting, plus printing costs, so you can hand sell.
And you need a website. Some authors sell directly from their site, or supply links so they get a referral fee. And a newsletter is a great resource to build your following.
Then there’s marketing. Of course there’s the DYI aspect of blanketing social media, networking with other authors, etc. But then there’s ads, which often are more effective. Book reviews are often done for free, but larger reviewers have begun charging. And there’s buying your own books to hand sell, take into book stores, etc. And swag, such as book plates, bookmarks, etc. And, if an indie bookstore is willing to have you in for a reading or a book launch, swag is generally expected. Also, if you plan to attend conferences, there’s admission, table rental, and purchasing books to sell.
Plus of course, your time, travel expenses, etc.
I have a friend who went with a small publisher and hired a PR firm to market her work, which is another option that seems to work very well, but expensive.
It depends on what your goals are, honestly. Publishing for fun is very different from building a career. It’s also important to note that unless your novel does INCREDIBLY well, you usually can’t take a self published novel to an agent or publisher. They want previously unpublished manuscripts.
For myself, it’s why I’m now signed with an agent and on submission. Self publishing is a LOT of work, and while I can do some of it myself, I know darn good and well that I need professionals for other things. Line edits and cover art for starters. I don’t currently have the time or money that self publishing needs to be successful, and that’s despite having several indie editors as friends who’ve offered a price break or payment plans. Depending on what happens with trad, I may end up trying a crowdfunding campaign to raise enough money for self publishing.
Self publishing is a fantastic path for many authors. I know a few who make a great living with it. But the ones who do were able to invest in the beginning. Readers are picky, and rarely give an author a second chance.