Your example is relevant to show how powershell can handle some tasks better, but this task is better performed with ip than ifconfig, as it has an option for json output which jq can parse:
ip --json link show eth0 | jq '.[0].address'
I'll admit that the discovery of this is probably not very great. I wouldn't be surprised if a number of people learned about the json output, and possibly jq, from this post.
PowerShell is simply inverting the defaults: Linux/Bash scripts output formatted text by default, but sometimes have options to return objects (often as JSON text strings). PowerShell cmdlets by default return objects (in a custom binary/in-memory format, but convertible to/from JSON, among other options like CSV and XML), but might optionally return formatted strings. (PowerShell also offers tools out of the box similar to but different from jq for exploring/converting/navigating objects.)
In general when working in PowerShell you don't have to look up if there is a command with a --json flag (or equivalent) that does what you need to do, you can assume that objects are the default response and move on to working with them with PowerShell's jq equivalents. (Obviously, that makes discovery generally easy.)
