Why cruiser sizes grew so sharply after the treaty era

Did any navy experience cruiser growth comparable to the United States after the treaty limits ended?

Not to the same extent; other navies expanded different ship types, while the Royal Navy still needed numbers of conventional cruisers rather than only very large ones.

The end of treaty constraints did not make every navy pursue the same larger cruiser. The United States built the Alaska class because it wanted an exceptionally large cruiser, while the Royal Navy still needed numerous conventional light cruisers for global duties. Other navies directed comparable growth into different ship types according to their fleets and missions. Size growth therefore reflects strategic and industrial choice rather than serving as an automatic measure of technical superiority.