Do all Magsafe adapters have removable extension cables? I have a 60W MagSafe charger (2012 Macbook Pro) and am wondering if the extension cord is removable so that I can just plug the actual "brick" into the wall with a fitted adapter? It doesn't seem like it's removable, so don't want to apply too much force - but would be neat if it is!
Yes. All Apple MagSafe adapters have universal / interchangeable connectors where you can use your preferred length and polarity and groundedness connecter of regional preference to mains power.


https://www.apple.com/shop/product/MD837AM/A/apple-world-travel-adapter-kit




The internal connector is standard IEC C5 or C7, and Apple adapters connect to the metal earthing pin optionally based on the cord or adapter chosen. Get a good photo of the gap, since a drop or crush can make the part very tight to remove.  The removal is quite linear with not a lot of play so hopefully you don’t have to break things to get it apart.