@derwinmcgeary I'd argue that even "just" for developers there aren't free stacks everywhere. In a lot of places yet but in VR for example we're still waiting for the Lynx who "should" be properly open, not stuck in an unrootable Android like the Meta Quest 2. This sounds niche but... what about what we all have in our pockets, mobile phones? Well until recently through e.g PinePhone we had Android (possibly deGoogled) or iOS or... non "smart" phones. It is slowly changing but I feel like trivializing the challenge of having "free" stacks (and I won't touch on proprietary drivers or firmwares) is a bit of shortcut.
@utopiah @derwinmcgeary You also need powerful hardware for phone development, that's an accessibility issue in a way too, because may people don't have the money.
I agree though that usability, accessibility & internationalisation (so that we can do proper localisation) still need improving. The big gap here is developer training. I have lost count how often I had to explain that "likes your post" is not a valid string to translate & how plural forms work in languages that are unlike English.