Assuming you have an Apple Developer account, you do even if you are a team of one. And you can’t notarize an app unless you have a developer account, so basically everyone who tries to notarize DOES have a team ID.
Because App Wrapper makes our life much easier. However, in the Packing pane you did have to define the Apple login and an app specific password for it to use to login on your behalf to submit to Apple. I believe it uses information from that to get the Team ID to use when submitting the notarization request to Apple.
Probably not though. The teamID is as to required for the old method. If you look at the command line options for this new notarytool program, they also give you the option of using Apple Connect Store API credentials.
The reason for requesting the Team ID may be one concerning ambiguity though. Working on my profile tool, I’ve found more than a few scenarios that can be solved by simply filtering on the Team ID.
NotaryTool is much MUCH better than altool. I switched from using altool in Terminal (clumsier) to creating and using my own customized AppleScript with NotaryTool on the inside, to run and notarize installers. With NotaryTool I’m able to perform the complete upload/download/wait-for-reply/staple and then run my own validation check on the notarized installer to finish.
NotaryTool is also faster, in terms of upload speed and response, than altool had been.
I hadn’t been aware of the migration from altool to NotaryTool, but once I did this (and did it “early”) it’s been a huge improvement.