In r-commerce (recurring commerce ... big number, small number of brands), the customer pays for Netflix and you pay your ISP or mobile provider money to have the service delivered to you. The customer pays for the merch and the customer pays for delivery. Customer pays x 2.
In o-commerce (omnichannel commerce ... probably another twenty or twenty-five percent of e-commerce controlled by 6-24 brands), the customer pays Best Buy or Dominos for merchandise and then pays Ford for use of a vehicle and pays Chevron for the gas used to get the customer to the store to pick up the merchandise. Customer pays x 2.
In a-commerce (Amazon commerce ... at least a third of e-commerce), the customer pays Amazon for merchandise and pays Amazon for Prime, at which time Amazon sends a van to your house. Customer pays x 2.
In b-commerce (e-commerce in a box ... Shopify / Big Commerce / MailChimp / Etsy / eBay / Marketplaces), the customer plays for the merch and in general the customer is being asked to not pay for shipping (read about Etsy for details) while the small seller is asked to eat the costs and then deal with UPS / FedEx surcharges and mysterious USPS delays. That makes it hard for b-commerce brands to make money.
In what is left of traditional e-commerce, the customer pays for merchandise (often discounted merchandise) and then the brand generally eats the cost of shipping. When UPS / FedEx tack on surcharges, it becomes hard for e-commerce brands to make money.
Given the forces above and the fact that a handful of brands control everything ... it becomes obvious that if you aren't part of the (b) (o) (a) (r) ecosystem you are being left behind, and that's what I'm talking about when I say e-commerce is burning down. BOAR is what e-commerce evolved into. If you are left in the (e) world, you need partners who help you, not ones who extract every last penny from you on the way out.