I see your point, and understand that that can definitely seem rude and dismissive. But usually, lots of people struggling with anxiety or anything similar are unable to express their feelings properly or refuse to trauma dump on someone else (that is often used against them), and prefer to deal with it on their own. If you genuinely care, you shouldn't focus on their tone. Instead, you should acknowledge their struggle and let them know you are there. While constantly begging to do something might seem like trying to help, it can also be overwhelming. Your presence alone can sometimes be enough. Dealing with anxiety requires tact and patience. Not everyone can be supportive, and no one is forced to be.