Even then, you would only be due the refund on 1 change fee -- the one that finally resulted in the ticket/flight that got canceled. It would not be a reasonable justification to be asking for the entire history of changes to be refunded.
True.
However, even a refund on one fee isn't something UA is going to give. I could sort of understand it if someone made the change in anticipation of WX in advance of UA putting out a waiver, then their flight would have ended up covered by said waiver--that would be worth at least contacting UA and explaining the situation. You might get a voucher (not a refund, though) for a similar amount as the change fee in that circumstance.