Gfilui

Because of this bug it's not possible to install powershell from apt for newer Ubuntu versions?

$ cat /etc/apt/sources.list.d/microsoft.list
deb [arch=amd64] https://packages.microsoft.com/ubuntu/14.04/prod trusty main
$ sudo apt install -y powershell
Reading package lists... Done
Building dependency tree 
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help resolve the situation:

The following packages have unmet dependencies:
 powershell : Depends: libicu52 but it is not installable
E: Unable to correct problems, you have held broken packages.

Actually, on closer examination, the documentation clearly states:

Supports Ubuntu 14.04, Ubuntu 16.04, Ubuntu 17.04

I'm on 17.10, what should the microsoft.list file look like from an artful system?

You tried to install the package for Ubuntu 14.04, which has libicu52 as a dependency, but Artful (exactly like Zesty) ships with libicu57. At least when it comes to the dependencies, the steps for Ubuntu 17.04 should work for 17.10. Luckily, Microsoft provides a prod.list file for 17.10 and 18.04 as well:

# Import the public repository GPG keys
curl https://packages.microsoft.com/keys/microsoft.asc | sudo apt-key add -

# Register the Microsoft Ubuntu repository – use your exact release only!
curl https://packages.microsoft.com/config/ubuntu/17.04/prod.list | sudo tee /etc/apt/sources.list.d/microsoft.list
curl https://packages.microsoft.com/config/ubuntu/17.10/prod.list | sudo tee /etc/apt/sources.list.d/microsoft.list
curl https://packages.microsoft.com/config/ubuntu/18.04/prod.list | sudo tee /etc/apt/sources.list.d/microsoft.list

# Update the list of products
sudo apt update

# Install PowerShell
sudo apt install powershell

# Start PowerShell
pwsh