I think if you watch a lot of TL games and observe Soulcas, it's pretty clear that his raw aim is one of the best in the world, but it drops significantly whenever there's any kind of pressure. He often hits insane shots in low-pressure rounds (like ecos, or anti-ecos, look at that Bulldog 3k vs Navi in the 2nd defense round for example).
That being said, he has had these issues for a long time, and he hasn't managed to solve them (and I'm pretty sure TL is one of the better equipped orgs in terms of support). At the end of the day, esports is a rough business and I think dropping him could be a good decision. It's a shame because as I said I do think mechanically he absolutely has the potential to be one of the best in the world. He just can't access it.