Exactly my thoughts. An annual show of the progress of scaling.
Talk is no good. It is best to show everyone. The same date each year makes sense incase any issues are caused with pushing things to their limits. Apps and wallets have advance notice of increased network activity.
Obviously if organic usage is breaking records on a monthly basis the previous annual test can be the last.
You can do all the testing you want on a dyno, you only find out true progress when you hit the track.