Rail service between China and Europe has greatly speeded-up delivery of your Ebay purchases as well as making it considerably less expensive than traditional delivery by slow-boat shipping containers.
Sorry, but nope. Cargo rail service from China to Europe (direct train) is two to three weeks, container freight via ship is about four weeks. Train is more expensive, so it is worth for bulk shipments where shipping cost counts, but also time to market (car parts from and to plants in china, laptops etc.).
Basically all the eBay/Aliexpress mail shipments go via air. They take 2 to 4 weeks to Germany because they spend most of the time waiting at some processing centers (first in china, depending on how many containers of mail are in line waiting for airliner freight capacity, then in Germany waiting for the postal customs processing). Btw., if you look at freight pricing, for small shipments (parcels, much-less-than-container-load), most of it is processing, transfer, local hauling, the long distance transport is only the smaller part of it.
Btw., according to Wikipedia, the Duisburg (Germany) to Chongqing train service, running more or less daily, transported 40000 containers in 2016. Well, one of the biggest container freight ships can load 20000 of these, so this one ship can do that in two roundtrips and 2 months or so. So the cargo rail service is a very useful thing, but serves a niche.