They could have used lower power Intel chips. Nobody forced them to put 45W chips in a paper thin chassis, but their marketing guys really wanted to have the top of the line Intel chips in them despite the wattage.
What did you expect would happen?
It would be like Apple putting the chip from the Mac Studio in the Air.
They did use low power chips. They had core M CPUs (later rebranded i5-i7 because OEMs). These were 4.5W TDP chips, even the best i7 in the 2017 model (i7-7Y75). The ONLY chips Intel had with lower power usage at the time were the significantly slower Atom and Atom derivatives.
What did you expect would happen?
It would be like Apple putting the chip from the Mac Studio in the Air.