This argument is about as flimsy as it gets. As Seboist pointed out, The Witcher III's predecessor didn't have a plot that derailed or simply entirely ignored the overarching plot of the series like Mass Effect 2 did for Mass Effect 3, despite the fact that, as standalone games, Mass Effect 2 was my favorite. That being said, I feel like it did irreperable harm to the series as a whole.
Why can I only give one like?
Much as I loved ME2's episodic adventures, it's flimsy main plot did nothing for the overarching narrative. I've said for awhile now that they could have retained the Suicide Mission structure more or less but the Reapers should have arrived in ME2. The plot should have been about heading off the initial invasion, not mucking about with DNA milkshakes and baby terminators with no apparent purpose. ME3 could then pick up in the midst of the War.
Ahem, but yeah, the
Witcher hasn't had the same sort of problem. Even if the issues in TW2 are pretty standalone, there is no shortage of continuation in the story. The only thing that worries me about the delay is that they might run into the same issues as DAI and release a buggy product, but I think Bioware will address the issues and I'm sure the
Witcher devs will too.