Can I erase a stolen iPhone without removing it from my account?

The iPhone is stolen. It has been replaced. Erasing the iPhone does not remove Activation Lock, so the thief cannot use the iPhone anyway without knowing your Apple ID and password.

Erase it immediately!

Erase a device in Find Devices on iCloud.com - Apple Support

You appear to have done most of the right things. NEVER remove the phone from your account and whoever has it will never be able to use it or access your data. If you haven't yet, you should contact your carrier and ask them to blacklist the phone if that hasn't been done.

Otherwise, you may receive emails which purport to come from Apple saying your phone has been found and you need to validate with your credentials. DON'T FALL FOR THIS. Apple doesn't get involved in lost or stolen devices and they will never send you anything like this. Also, the thieves may attempt to threaten or frighten you. DON'T FALL FOR THAT EITHER.

As long as you had Find My enabled, which it appears you did and you used a passcode on the phone, your data can't be accessed.

You're welcome and I'm sorry this happened to you. Sberman recommends you erase the phone immediately. From your first post, I got the impression that wasn't an option you saw? Erasing the phone would be good if you can. Just NEVER remove it from your account.

Your phone is bricked as long as you do not provide anyone your Apple ID and Password to unlock it. That is the reason for the warning to be aware of a phishing attempt from the thief claiming to be from Apple. The address that is shown is the last known location and you are only given the option to cancel the erase request because it has not been online to perform the request already. If it ever does come online, the erase request will be processed and the location updated.

Peacecircle wrote:

The insurance company AIG's claim form seems to indicate that if I were to find the phone, once I submitted the claim, I would not be able to use it again.

The insurance company will probably say something along the lines of – if you make a claim, and we ever get the phone back, it's our phone now.

Chances are that neither you nor they will ever see the phone again, but you can at least "brick" it for the thieves. My understanding is that Apple also has plans in the works to extend Activation Lock to parts, which hopefully will make life a bit more miserable for some of the "chop shops."