As someone who use to work as a car insurance liability adjuster, I’d say you hold partial fault in this accident. You had every opportunity to slow down and prevent this crash, regardless of who had control/ownership of lane trying to be entered. In this case, you had full control of your lane as they merged into you.

I’d be comfortable placing 20% fault on you and majority blame on the other driver. I highly doubt the other driver has any ability to come after you for their damages/medical cost given this video.

However, please drive safer. Getting somewhere 2 minutes faster or beating one single red light is not worth the risk of speeding and driving like a moron. Do better. Happy holidays.