I follow a tax guy on Twitter and he said it is because of regulations.

I just wonder why Intuit can't have some local model and do it within guidelines.

And you can add me to the list of people who ran my tax filings through AI and found mistakes.

Most were the CPAs fault but I forgot to include a local folder when uploading and codex was able to recognize that my CPA did not include those forms.

I would not advocate replacing CPAs with AI but they can definitely fact check the CPA.