Initializing a new (or power-washed) android/ChromeOS device _requires_ a Google account, so if you don't have one (or claim not to) they device initialization process will generate a new Google account for you. Even if there's no phone number or SIM card in the device.
I've had a number of Android/ChromeOS devices over the years, and I've had each one generate a new Google account. None of these accounts have phone numbers associated with them.
I generally don't use these accounts for much more than downloading free apps from the Google Play store -- maybe more extensive use would trigger a "You must add a phone number to this account to proceed"?