If you have an iPhone 6, iPhone 6 Plus, or older iPhone, you won't be able to get new versions of Opera on your device. That's because the Opera for iOS app will no longer work on devices running iOS 14 or earlier. The iPhone 6 series is the last device that won't be able to upgrade to iOS 15.
Additionally, iPhone models up to the iPhone 12 series ship with iOS 14, so if you’re still running this older version of the operating system but want to stay up to date with Opera’s latest releases, you’ll be forced to upgrade to a newer version of iOS. Not only that, running older versions of iOS is also unsafe, with many unpatched security vulnerabilities.

Opera says it supported iOS 14 for as long as possible, but technical limitations forced the company to end support for the operating system at this time. Opera 5.4.2 is the last version that supports older iPhone devices. If you have an older device that can't be upgraded to iOS 15+, you can still install supported versions of Opera (not the latest) by going to Account > Purchase History . However, you should only do this if absolutely necessary.
Apple released iOS 14 in September 2020, during the COVID-19 lockdown. It's been almost five years now, so upgrading to the new version is worth it if your iPhone is still running iOS 14. Most Apple devices that Opera still supports are capable of running iOS 15 or later, so upgrading is a viable option for those who want to continue receiving Opera updates.
Opera has been notifying users of iOS 14 and below about the end of support for over a year now. The company's stance is that users should upgrade to a newer version of iOS if possible, as Apple stopped supporting iOS 14 years ago, and now Opera is following suit.