> 30% of iOS users aren't updating for whatever reason
That is not what the figures show. The figures show that over 90% of iOS users are upgrading. I believe you’ve mistaken are not on the latest version with aren’t upgrading. Those 22% are upgrading, it just takes them 12–24 months to do so.
> so they have an outdated WebKit with known vulnerabilities.
This is not true. Apple pushes security updates for old versions and includes a setting so that phones can auto-apply security patches even if the user doesn’t want to do a full upgrade to the latest version automatically.
Only people on the latest version get the latest Safari, that's the relevant number.
And I already addressed older versions. They get updates but only for vulnerabilities that Apple "is aware" are being exploited in the wild, not all vulnerabilities Apple has fixed in the newest version (yet Apple isn't omniscient about what gets used in the wild). And no updates for rendering bugs, as far as I'm aware.
That is not what the figures show. The figures show that over 90% of iOS users are upgrading. I believe you’ve mistaken are not on the latest version with aren’t upgrading. Those 22% are upgrading, it just takes them 12–24 months to do so.
> so they have an outdated WebKit with known vulnerabilities.
This is not true. Apple pushes security updates for old versions and includes a setting so that phones can auto-apply security patches even if the user doesn’t want to do a full upgrade to the latest version automatically.