If the choice is either a $10,000 tax refund or smaller withholdings (e.g., getting a slightly larger paycheck throughout the year), of course it makes more economic sense to pay yourself a bit extra every paycheck.

But if that extra money is going to sit in a savings account (which it likely would) earning 1%, the extra income would result in a whopping $50 at the end of the year (or $4/month). Very inconsequential. And that's assuming a $10,000 refund, which is larger than what most people would be dealing with.

So if someone has some non-economic reason to prefer a larger refund (e.g., if it just feels more like a happy surprise to get a large refund than to watch the savings account slowly build, or if they are more likely to do something fun/productive with the refund money than they would with the additional savings, or whatever their rationale), so be it.