Is ExpressionEngine dead?

Not even close. In fact, I would say it's now leading the way on self-hosted CMS features and user adoption. With the change in management between version 5 and version 6, EE has come alive again and has pushed the boundaries of what CMSs can do. It's introduced frontend editing, new role management, and a number of features that used to be 3rd party. Now is the best time to be using EE.