Alternatives to Amazon.com? I'm totally serious when asking about this. I think delivery apps (like the one comically named "Deliveroo") are all potential alternatives to Amazon, but I think they charge a premium.
For clothes Zalando is a big one.
Beyond that it gets fragmented into companies serving only a few markets. Alza, Cool Blue, and Media Markt are some that come to my mind.
In DE probably Otto.de is the closest you get (?).
In NL I remember Bol was quite good.