The question on that page to which your quote answers is, "Is my device only running free software after I install Replicant?" I've emphasised the word "device" because this question portrays a different context: open hardware vs open software. From one point of view, you're absolutely right. The devices running Replicant do not only run free software after Replicant is installed because firmware, which is closed, is indeed a form of software. On the other hand, whilst embedded bootloaders and firmware aren't free, they do not form part of the operating system and do not ship with Replicant. The devices that Replicant runs on are not 100% open but that does not mean that Replicant is not fully free.

Replicant is distributed without any proprietary code. Functionally is indeed incomplete but you have an operating system that is entirely free which still has many uses.

We're getting a little bit off topic here. The intention of my initial rant was basically to highlight that Android is a horrible OS with many problems (not only binary blobs) and Halium does not help very much with resolving them. Instead, it facilitates in bringing the same problems to GNU/Linux distros. I don't really understand the purpose of running GNU/Linux on our phones if it comes with practically everything I hate about Android. If it's for the software catalogue, you'd probably be better off with just purchasing the Android phone you desire and running a Maru OS chroot.