No surprise there. The soundtracks have been consistently great throughout the entire series. They rank among my all-time favorites for game music, especially TW1.
I started to play the Witcher series because the main theme for TW2 made me almost cry when I heard it for the first time. Have finished all games in the series multiple times since then. I found the soundtrack for vanilla-TW3 a bit disappointing after TW2 which was my favorite game music soundtrack until Hearts of Stone came out. That melody and the children's song is just an absolute masterpiece in so many ways. I still can't believe how well the melody describes the story and you-know-who in the DLC. I have listened to the Witcher 3 concert hundreds of times and it is among my favorite classical music performances. Really looking forward to the soundtrack of Cyberpunk. It cannot be equally good (because the Witcher soundtracks are just stellar for the entire series as you say) but if it is even close, it will become my favorite sci-fi game soundtrack.
On-topic: I wish they'd add GeForce Now support for GOG games. I really rather bought directly from them but it's more tempting to buy from Steam because that promises direct support for GeForce Now. There is no way my computer will be able to run any of the AAA games these days.
PS. I am aware that you can go around the GOG/Geforce Now issue and might try it with Cyberpunk.