iOS 18.3.2 Broke iCloud Mail Delivery

The iOS 18.3.2 update that Apple released last week appears to have broken iCloud Mail for some users. There are multiple complaints on Reddit and the MacRumors forums from users who say that ‌iCloud‌ Mail is not able to push new ‌iCloud‌ emails to their iPhones after the iOS 18.3.2 update.
Affected users say that despite having the correct settings enabled, new ‌iCloud‌ emails are not showing up in their inboxes until a manual refresh. From a Reddit user:
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