I don't think anyone is proposing removing the ability to not install with nonfree packages, merely whether the default should remain as it is.
Personally, while I would prefer to be able to change and replace the software running on the tiny computers that make up a modern system, focusing on the distinction between "the vendor shipped it on a flash chip so we don't have to think about it" and "we need to load it at runtime" seemed a bit like spending too much effort on too little reward, to me - if we convince the manufacturer to up the cost by a few cents to hide the firmware blob from us, is that really a victory for Free Software, simply because we don't have to think about it? (Particularly if it sometimes results in never having ready access to a mechanism to replace the firmware blob, should someone sufficiently motivated either convince them to Free it or develop a replacement?)
It's great whenever someone develops replacements bits or, even more rarely, convinces a company to release their firmware bits permissively, but without a list of examples of Debian's stance changing the policies of other organizations, I think it's not that effective a tool for changing behavior in this case, and instead primarily inconveniences people who want to use Debian.
Whether they end up changing the default behavior or not, people in this thread replying "wait, there are firmware-bundled images?" makes me think Debian should either stop making them or stop making them so unintuitive to discover.