Is it possible to downgrade reminders?

I’m using an iPhone 11 with iOS 13.5 and a MacBook Pro with macOS Sierra. I have been holding off on updating my reminders app because of my older macOS version.

Yesterday I upgraded to macOS Mojave (10.14) and upgraded my reminders app on my iPhone, not realising it only works with macOS Catalina (10.15). I am not going to upgrade to Catalina any time soon, but not being able to use reminders on my MacBook Pro is enormously disappointing. I’ve reset my iPhone and recovered it from an iCloud backup that was made before the update but this didn’t solve the problem.

Anybody got any ideas about how I could downgrade my reminders app so I can use it on my MacBook Pro with Mojave again?

Thank you