1. Good jobs are hard to find, so some people try to make a living instead by influencing what other people buy, in exchange for kickbacks from the sellers.
2. The sellers offering the largest kickbacks are never the sellers offering the best value for money, because if they are, a reseller can buy the products from them, charge a higher price, and spend some of the markup on kickbacks to product shills. This results in a systematic bias toward overpriced junk in heavily advertised products.
3. While some knowledgeable people do still take the time to share their knowledge and unbiased judgments, which is for example mostly how Wikipedia is written, Google and other search engines are increasingly directing search traffic to the product shills instead.
I agree with you that, given problem #1 and problem #3, problem #2 is sort of inevitable, and all three problems tend to mutually reinforce each other. But I think we could reduce either problem #1 or problem #3 by an order of magnitude without significantly reducing the other one. In particular, we might not be able to completely solve the SERP quality problem without solving the jobs problem, but I think we could improve it enormously just by writing a better search engine, which is an easier problem than fixing the entire economy.
I'm sorry to hear you're back on the streets, and I hope your situation improves before you die. I'm glad you're not dead yet because I often find your comments insightful. Happy new year!