How so? Did you miss the major snow storm in atl and then up the east coast? One could make the case that without the law (whether or not airlines cancelled because of it) airlines might have been in a worse spot had they kept flying, using crews, etc and trying to then recover with dislocated planes, timed out crews, etc. Remember management sells cheap tickets because that's what they do. Pax aren't idiots for buying them. Besides data shows that are no more cancellations before or after the law. It Seems the OP is happy many pax had flights pre-cancelled because they bought cheap tickets and now deserve what they got when in fact most pax ended up less inconvenienced due to the pre cancellations.
The dozen family members and friends I spoke with who all had cancellations a) had never heard of the 3 hour rule and b) all were Generally happy with the action the airlines took well ahead of the massive storm, versus getting stuck at the airport. Yes, it's a stoopid rule, especially how it was ramrodded through by a vocal minority and the media. However I don't see passengers as stupid for buying the cheapest ticket they can find. Blame that on management trying to under cut one another in an effort to pad bonuses. Now paying $150 to check bags, that's ok as many travel with furniture.