The article title is very misleading, although technically correct. High volume doesn't mean they won't be making chips on it -- they will, but only their own products, and products for other customers will follow.
Also, not noted is that 18A is a refinement of 20A, which is already running -- 20A will never go into volume production because all the fabs that make it will turn into 18A during 2025. As such, 18A will seem lower volume, but the truth is that it's "prototype" process, 20A, will be running in parallel, in 2025.