You're misinformed. Also, that's quite the assumption that most of use don't realize what Interplay used to be. The reason most of the die hard's are here is thanks to Interplay being the first to sell their classics here on GOG, all the way back in 2008-09. I'd say most of us very well remember Interplay's glory days.
The Alone in the Dark ip is currently owned by Atari, and Another World is owned by a company called Digital Lounge, and they released a 20th Anniversary Edition already. You can find both here on GOG.
Blackthrone is owned by Blizzard and iirc is freeware on their service now. Bard's Tale is owned by inXile Entertainment.
As for the D&D games and Star Trek games, those are both licensed, meaning multiple companies own the rights. Fallout is completely owned by Bethesda, who went through a lengthy court battle against Interplay. Pretty sure they don't own Fragile Allegiance either.
From your list, I count only 9 titles they actually own. None of which would be beneficial for CDPR. I already see publishers speaking about these IPs, and Devolver even put up a poll on Twitter asking which one they should grab (Earthworm Jim was winning).