Interesting thread. I like to occasionally stir a bit of marmite into stews but not keen on spreading it on toast.
On the trad vs. self-publishing question, I was reluctant to go down the self-pub route because of not being entirely confident that all my grammar and formatting would be right (yes, I know you can pay for a freelance editor and proofreaders etc, but that feels like a huge expense) and also knowing it would be steep learning curve to do things like register for an ISBN etc. I also don't much like supporting the Amazon monopoly and try to avoid buying stuff from Amazon, so I was reluctant to just go down the KDP route.
I've been lucky to find a very small indie publisher who's agreed to take on my novel(s), having read my first MS. I keep all the rights, they do the bits I don't understand very well, and publish my book for me as PoD and ebook on various platforms (yes, including the dreaded Amazon, but not exclusively them). I'm not expected to pay anything and we share any profits 50/50. They'll also create cover artwork or you can source your own - I decided that was one bit I'd spend some money on. I'm not published yet but I've been very pleased with the attention to detail and the professionalism. The final text is currently being proofread by a couple of other authors with the same publisher. I'm now contributing to the 'cooperative' by looking after the social media accounts. The publisher is open about the fact that they don't have time to do any marketing so now some of us are working on building the profile a bit. It's feels good so far to be part of a community of authors working together to publish and promote each other's work and to benefit from one another's expertise. Maybe that's the way forward - cooperative publishing houses, rather than every author going it alone.
I know I'm never going to achieve the level of exposure and distribution I might have got if I'd succeeded in getting a trad deal, but my book is going to be available to buy, might one day recoup the cost of getting a nice cover design, and I'm enjoying the experience.
All that said, even small indies are finding themselves flooded with submissions. Another that I submitted to admitted that a year ago they'd have probably offered me a publishing deal but didn't because the volume and quality of submissions was going up and up and my submission just wasn't quite right for them.