as for S
I don't like it, but compared to 5e canon, he is a homeless drug-addicted priest of Bhaal who lives on the streets of BG city, tormented by his immortality.
That was bad, and mean spirited and gross. Him being a powerful cult leader and a grandfather, it undermines his ToB story but it's better than M&BBoV
I can kind of see how, if he became lost he could find identity and power in the cult of bhaal, even if he doesn't believe those who do worship him and it's not like he can return to the Iron Throne. So I guess it works?
But isn't the Minsc & Boo's Journal of Villainy rather dubious canon? Like there were some vague similarities between it and BGIII that might have indicated that the author's sat down together at some point early in development, but even if that was the case they split from there pretty drastically since then, I would think. One of the big 'reveals' from the book was that a certain character was
Edwin, and that didn't pan out from what I hear, the wizard is just someone else, and the Iron Flask plot goes nowhere like the Minsc and Boo version does
Point being, I don't think Larian was ever 'obliged' to do S the way they did. Pretty Sure V's story was pretty different from M&B's version as well (and more sympathetic).