As an iOS developer I can say that I've never tested my apps using VoiceOver. Not because I didn't want to spend the time or figured it was such a small part of the market that it wasn't economically viable. The thought literally never entered into my mind. I never thought someone who couldn't see the screen would ever interact with it.

This has made me think of other minority groups that I may have been discriminating against. The colorblind, the deaf.

"I didn't know" is almost never a valid excuse and it most certainly isn't in this scenario.

Apple really should consider adding accessibility testing to the app approval process or working with a group to provide it in parallel.

Maybe it wouldn't result in the app being rejected but Apple should provide developers with feedback about potential accessibility issues.