That the person who reported it used a ML to try and find the setting to attempt to solve it, did not fill me with confidence of their abilities to manage this. They later admitted that they did have it enabled in some form.
They also never became specific about how well Gemini interpreted their tax result file. Did it give the proper number verbatim? That’s pretty damming. Did it just reply “You’re not getting a tax return”? That’s just 50/50 odds.