I'm not sure if it's actually required by law, but usual retailers have been communicating a lot on this in the last year. Most of them display a sticker in their stores, but the score is also prominently shown on their websites[0][1]. I'm really not surprised that a lot of people willing to buy something noticed the repairability score, because it's near impossible to miss it.

[0]: Some examples on two of the biggest appliance/electronics retailers: https://www.boulanger.com/ref/1157777, https://www.darty.com/nav/achat/gros_electromenager/lavage_s...

[1]: One last example on the Orange (mobile services provider) shop: https://boutique.orange.fr/mobile/details/oneplus-9-pro-5g-n...