Honestly, you don't need an insider in CDPR to understand what happened. Obviously it is hard to predict exactly the specific factors that combined to cause Cyberpunk to fail, but in retrospect the signs were very visible.
CDPR has never been a good company with system implementation. Witcher 1 and 2 had minimal interaction with the environments and NPCs. When they tried to do something more "ambitious" in Witcher 3, the illusion of world began to break down. There is virtually no AI behind the reactions of the NPCs and not coincidentally, there are no major events within the cities of Witcher 3. This is because the NPCs are not programmed to react to anything other than a bump or a huge noise (magic). CDPR tries to disguise this by placing fights inside enclosed environments within the city, isolating you from the rest and conveniently removing any NPCs from the area before the fight.
The point is, Witcher 3 is actually less interactive than any Bethesda game. It disguises how shallow its mechanics are with clever storytelling choices, separating conversations between characters in one space and combat in more distant areas. But the total lack of systems, which is not that noticeable in Witcher 3 because the game made you focus on other things, becomes impossible to disguise in an urban environment, within a city. They tried to go beyond their league, and failed. Bethesda/Ubisoft/Rockstar have, for decades, made iterations of their worlds and carried over the accumulated systems from previous versions of their games. CDPR underestimated the size of the job, and the incompetence of the managers added to the failure. The stupid attempt to make the game run on previous generation consoles was just the cherry on top.
Edit because I don't want to post again:
Elden Ring isn't bursting with physical simulation systems either. You don't need to do every prestige feature if the game shines somewhere else.
The reasons that make Elden Ring work are analogous to the reasons that make Witcher 3 "work" as well - the setting in design of the environments. Elden Ring does not need a traffic system, a police/crime system, a system that controls the reaction of dozens of NPCs to any generic character action, etc. Cyberpunk needs that to make the game's world work in a city, in an open-world environment, and, because it doesn't have that, it failed. Hell, even Zelda BoTW has NPCs that are little more than cardboard decorating the villages, but it works because you don't have to interact with them in other contexts.
Cyberpunk should not have been an open world game. It probably would have been an infinitely better game if it was more like a Deus EX, with main hubs where you would have the character interactions and the dungeons/instances where you would accomplish your quests/missions. But hey, being "open world" is what brings in the big bucks and it worked in the previous game, right? And again, it is exactly because they think like that that what happened, happened.