Muted means softened and quiet, not bold. Sound turned down, or colour turned down.
The sound sense is literal, since a muted television has no volume and a muted trumpet has a device pushed into the bell. The colour sense is about palettes, and muted tones means soft and greyish rather than bright, which is the standard vocabulary of interior design. There is a third sense about reaction, since a muted response means a disappointing one, and that use is common in reviews.
Latin
mūtus
Middle French
muet
Anglo-Norman
muet
Middle English
muet
English
mute
English, today
muted
Built from
mute comes from Middle English muet, from Anglo-Norman muet, moet, Middle French muet, from mu (“dumb, mute”) + -et, remodelled after Latin mūtus.
Etymology from Wiktionary, CC BY-SA