The big pain, historically, has been network device drivers.

Ubuntu does more or less does this. But the crucial step is having a checkbox in the installer to install the non-free drivers (that are shipped in the installation media). Otherwise you might have a computer with linux but no easy way to get a driver for your wifi chip to it.

One issue with that strategy is accessibility; e.g. a case that was actually cited at the onset of the discussion that lead to the vote are blind users that need specific firmware to use their audio interface, without which they simply cannot use the installer

Yes, but I suspect that the vast majority of users would find this annoying.

Back in the day when I was playing with Slackware, it would have been interesting and I wouldn't have minded in the least.

But these days, if I'm installing a distro, it's because I'm being paid to do a job. And that job has nothing to do with the distro itself: that's just a hopefully minor step along the path. The fewer "just go do this one little thing" speedbumps I encounter, the better. Or I start to get frustrated and irritated and wonder if there isn't an easier way.