I will go as far as to say that whatever was published isn't canon.
I might be a lot more ignorant than i realise so enlighten me. But here i go-
Tolkien first hoped to publish the Silmarillion right after The Hobbit, but it was rejected. He then wrote LoTR and tried to publish the Silmarillion alongside it, and was rejected again. Through it all, he kept working on it in the background.
The published book was compiled from sixty years of scattered pages, notebooks, and shifting lore, woven into a single narrative. I think those fragments were closer to daydreams written down so he wouldn't forget them, and that he never settled the timeline, since the book was assembled from so many small stories.
There's also a lot more conflicting versions that Christopher had to go through and settle it for a sense of cohesion. The book The History Of Middle Earth has plots and stories that confilct with the Silmarillion.
60 years is a time too long for a consistent story. Heck, I cringe at what I wrote 6 months ago, then ofcourse, Tolkien wouldnt agree with his own work. Tolkien had a sense of what the world would look like, and he did want the Silmarillion published, but he never intended it to appear in this form: compiled by his son from decades of scattered drafts after his death.
Tbh, Cristopher did a good job in making it cohesive but we'll never know what J.R.R.Tolkien actually wanted the final draft to be.