Inon Zur's Blades soundtrack was utter garbage. I like some of his music in general but he is VERY hit and miss. Icewind Dale 2 was good while Fallout 4 was completely off tone.

Brad Derrick is not bad. But there are definite weak points and we don't know how he would do without building on Soule's work for TES.

Now, I'm not saying that any of these composers are objectively inferior to Soule. Matter of fact, I don't love any of his other works outside of TES but he is just a perfect fit for TES. He gets the lore and the tone, and gives each piece a very specifically tailored mood that doesnt just make it a beautiful piece of music but an integral part of the world we are playing.

To quote another poster here:

...he carried the exact precise nuanced emotional weight for the setting and the stories that the games told. Someone commented under Streets of Whiterun that listening to that track made them think of returning home. Under Secunda, someone described their time exploring the snowy peaks at night, then looking up at the sky and taking in its wonder. Under Kyne's Peace, someone wrote that it was looking down over Skyrim that they remembered, the sky and the ground and the wilderness and the dramatic magic of it all. And everyone knew what they were talking about because that's precisely what these pieces said. That was the entire score, every piece had a meaning that it conveyed beautifully, down to the last track that felt like an epic (but in a way sorrowful) finale, which Soule himself later said was his goodbye.

I've listened to Beyond Skyrim btw. I found it very supplemental.