"It is marketed that Teams would consume 2x less memory as a result of the transition." Not sure if that's the article or the statement from Microsoft, but what does 2x less memory even mean? Half the memory? Quarter? If so, why not just say that?
E.g. if Teams used to use 95% of your system, now it uses only 90%.
Technically 2x less could be the opposite of 2x more, and technically 2x more means 3 times as much. Really what I think this shows is that it is much nicer to talk about factors than it is to talk about relative in/de-creases.