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Isn't it a bit odd that The Witcher 3 is not (yet) available through GOG when we have it on steam?

For the record, I already complained a long time ago about the issue that we cannot have The Witcher 3 from steam on GOG (unlike 1 and 2) and said it would force me to buy DLC on steam instead of GOG, since I have the base game on Steam. Time passed and I did actually buy all DLC on steam.

I was positively surprised to see this GOG steam connect new feature. I noticed it is mentioned that it is up to game editors. So WTF CD Projekt? Still not enabling your own customers to use your own platform? How is that good business?
My impression of GOG Connect is that it's mainly for older games, where most people who are interested in the games already bought a copy somewhere. If they would add Witcher 3 (which is still a top seller), new customers would simply buy it on Steam and connect it on GOG and GOG would stop earning money with their flagship game.
i would gladly trade my steam version for gog then.