There was a trending tiktok by economist Kyla Scanlon on the topic of "subsidizing affluence" and how these services were able to be offered so cheap because of incredibly low interest rates and investment. Rates have risen dramatically, affecting both the appetite of debt for start-ups and the spending power of consumers. Shareholders recognised this, and it showed through Deliveroo's historically bad IPO.
Ultimately, I suspect Deliveroo will continue to underpay (relative to the cost-of-living) because of the poverty trap — poor people don't have many options, and being underpaid as a Deliveroo rider may be the only option for survival in London and other similarly major cities.