It is disappointing that even BW does continuity better than CDPR :/
I wouldn't say that for Mass Effect or Dragon Age to be honest. ME3 contained major character assassinations for all kinds of characters. To name a few, Ashley, Udina, Samara... the list goes on, and that's not to metion there was several retcons.
The only retcon per se I've seen (which can be explained somehow) in TW3 is what the hell Roche did with Anaïs between Witcher 2 and Witcher 3, because she's nowhere to be seen.
Even so, I still feel like there was a better sense of continuity between the three Mass Effects than the three The Witchers. I think it's because at least Bioware did do some exposition on why ME2's plot started the way it did after ME1... but IDK. A lot of people flack on ME2 for either A) "having no plot) or
being an awful continuation. The main reason for the latter statement is that ME1 ends with Shepard going "we're gonna find a way to stop the Reapers!" and Udina/Anderson's last words are something like "We're gonna stop those Reapers!" too but then ME2 sets up the plot by saying "nobody believed Shepard so now he's hunting geth".
Perhaps Mass Effect is better of a continuity than Witcher, but to say either one is ideal would be so wrong. I think we have yet to experience a good, consistent, continuous video game trilogy, even after this. (But if you think Witcher or Mass Effect were perfect trilogies, then more power to you!)