I've never had to deal with it in my game, either, but I assure you there were quite a few people that wound up with inventory issues because of this inherent limitation of the engine. There were even some members of the community that built a utility to help (PC players at least) recover a functional save if it happened. But there is no "fix" for it -- it's just not how the game was designed. It sounds like it may be a manifestation of the same type of thing here.
So what you are saying is the devs learned absolutely nothing from The Witcher 3 and the issues save files caused there, and they just went ahead and screwed the new game from the start once again. Does not seem very wise;
If people are having these save issue just a few days after the game is released if this is not fixed asap there is a huge shitstorm coming towards the devs once tens of thousand of users start having these save issue as they progress through the game; its not a question of 'if' it happens but rather 'when' and for the sake of CDPR lets hope they have a solution before then.