I think we're going to see different AI tools optimized for different stages of the development workflow, with developers assembling and using a collection of them, just like they currently assemble a collection of tools for different tasks within the stack (backend language, frontend language, database, cache, infrastructure, etc.). It's unlikely that there's ever going to be one AI coding tool to rule them all.
As someone building (and frequently using) an AI coding tool that is very much focused on development time[1], I still also use GH Copilot and ChatGPT plus heavily as well. In a team setting, I could definitely see using my tool in conjunction with Ellipsis too. A feature built partly (or entirely) with AI still needs PR review. And an agent focused specifically on that job is likely going to be better at it than an agent designed for building new features from scratch.