Installation instructions inconsistent

Is silently deprecated?

I install Discourse as part of my business. My script installs Docker with

   wget -qO- | sh

Which appears to install docker-engine. But this install doc claims

Is no longer a good way to, Get Docker?

And what about Docker-compose?

Perhaps it should be another topic, but why do Mac & Windows users get docker-compose when they install docker-ce, but Ubuntu users don’t? It seems bizarre that the instructions for installing docker compose on Ubuntu (that I can’t link to as a new user) say to just curl today’s docker compose into /usr/local/bin and without any means to get future updates.