A bit criticism to the Silmarillion is that the style is very dry and the plot is disconnected.

This is by design. The Silmarillion wanted to be the creating work of the UK mythology. As such, it mimicked the style of other mythological sagas: the Mabinogion most notably, the minor Homer, the Eddas. Part of the idea is to create a shared well-know scene from which other authors can draw to set their own works.

In some ways, it was incredibly successful: nowadays it’s impossible to talk about Elfs without referencing Tolkien’s in some ways.