The Jones Act was not related to the AK gold rush, which had been over for ~20 years by the time the JA was passed in 1920. Rather it was an attempt by Seattle ship operators to fend of Canadian competition in the Alaska trade. Until the JA was passed, goods could be transported between the Lower 48 and Alaska via Vancouver. Seattle shipping companies—more specifically, the Pacific Steamship Company—hated this competition and enlisted the help of Sen. Wesley Jones of Washington state to get the law changed. What was eventually adopted as the JA—Section 27 of the Merchant Marine Act of 1920—is almost exactly what William Clark of the PSC proposed during a February 1920 congressional hearing. You can read more about that here:
As for the PVSA, a GAO report identifies competition from Canadian vessels on the Great Lakes as the impetus for the legislation's passage: https://www.gao.gov/assets/a241568.html
"The PVSA was originally designed to prevent U.S.-based vessels from facing strong competition in the domestic transportation market from maritime nations, such as Great Britain and Canada. Specifically, there was a concern about competition from Canadian vessels that were transporting passengers across the Great Lakes. The PVSA originally stated "no foreign vessel shall transport passengers between ports or places in the United States, either directly or by way of a foreign port, under a penalty of $2[Footnote 19] for each passenger so transported and landed." Congress originally thought that the $2 penalty per passenger would discourage this practice."
This comports with Charlie Papavizas's new book Journey to the Jones Act: https://www.amazon.com/JOURNEY-JONES-ACT-Merchant-1776-1920-ebook/dp/B0CZPD797V