I have model A2084 (AirPods Pro 1st gen) but with installed firmware 5B58, is this a bug or a mistake in this page?

Hello puccet,

Welcome to Apple Support Communities!

We want to help get the firmware updated to the latest version.

We see you viewed the Apple Support page for About firmware updates for AirPods - Apple Support

From the link you visited, let's make sure you've used these steps to update the AirPods:

"Firmware updates are delivered periodically while your AirPods are charging and in Bluetooth range of your iPhone, iPad, or Mac.

Because firmware updates are delivered automatically, you don't need to update your AirPods.

To use your iPhone or iPad to check that your AirPods are up to date, make sure that you have the latest version of iOS or iPadOS. Go to Settings > Bluetooth, then tap the Info button  next to the name of your AirPods. Scroll down to the About section to find the firmware version.

To use your Mac to check that your AirPods are up to date, make sure that you have the latest version of macOS. Press and hold the Option key while choosing Apple menu  > System Information. Click Bluetooth, then look under your AirPods for the firmware version. With macOS Ventura, you can also choose Apple menu  > System Settings, click Bluetooth, then click the Info button  next to the name of your AirPods."

It's possible they have just not updated yet.

Please let us know if you have further questions.

Cheers!