Erase iPhone 15 Pro Max data after theft using Find My

No one can get into your phone unless they can guess your correct passcode in less than 10 tries before the phone locks out and will not even allow any more passcode tries.

As an extra precaution, you can erase the data on the phone as you have done.

What is important is to not remove your phone from the list of devices that are using your Apple ID. If you do this, this will remove Activation Lock and give the thief permission to set up the phone as their own.

True, you will never see the phone again, but you can really frustrate the bad guys by not removing the phone from the list of devices using your Apple ID.

Be extremely careful if you see a message or email stating that your phone has been found and you just need to provide more information so the phone can be returned to you. Apple does not get involved with lost or stolen phones, so any message like this is a scam that is trying to trick you into providing personal information to remove the lock on the phone.

Yes.

Although if your iPhone was protected by a truly secure passcode (at least 6-digits, known ONLY to you, and not easily guessed), it could be argued that remote erasure isn’t really even “necessary.”

(All data on your phone is encrypted and unintelligible w/o manual passcode entry)

For additional steps, see:

If your iPhone or iPad was stolen - Apple Support

That is fine to erase your data. With your iPhone protected with a Passcode there is no chance that any of your data would be able to be accessed as long as that passcode was not something like 1111. The device will lock if there are too many attempts to enter the passcode requiring complete device erasure.

Just make sure you do not remove the device from your account. That is what would allow the thief to set the device up as their own. Your data would still not be able to be accessed because that would also require the device to be erased. Erasing the device does not remove the Activation Lock, so as long as you do not remove it from your account, it will be completely useless to the thief.