Yes – with caveats. You can absolutely install and play Minecraft 1.15 on an older iPhone or iPad, provided you:
For nostalgia, offline play, or preserving the Buzzy Bees update on a legacy device, the Minecraft 1.15 IPA remains a working solution. However, always prioritize device security and ethical sourcing. minecraft 115 ipa work
Best for iOS 14–16.7
Since you specifically want version 1.15, you cannot use the latest launcher defaults. You must downgrade. Yes – with caveats