“laptops” run on windows while Chromebooks use chromium or whatever… it’s more like using a phone. Not paying for the windows licensing helps keep costs down.
Another method of keeping costs down is to use underpowered components, as you mentioned, so I’m guessing some users would be disappointed with their new chrome machine when they discover it can’t play high frame rate games at 1080 while streaming Spotify and have 10 browser tabs open in the background. This standard establishes a phrase consumers can understand rather than them trying to decipher the technical specs themselves.
