I mean the headline in your linked article literally calls it the 'minimum system requirements' not 'reccomended'. Games have had two sets of requirements for decades, I don't see why they couldn't do the same. Regardless if you need to run Linux on older/less powerful hardware there's much better choices than Ubuntu, which is designed to be as beginner-friendly as possible at the cost of performance and customizability as is, so in their case I guess it kinda makes sense to dumb it down.