The following is the Jan 19, 2021 Congressional Research Service report, Navy Ship Names: Background for Congress.
From the report
Names for Navy ships traditionally have been chosen and announced by the Secretary of the Navy, under the direction of the President and in accordance with rules prescribed by Congress. Rules for giving certain types of names to certain types of Navy ships have evolved over time. There have been exceptions to the Navy’s ship-naming rules, particularly for the purpose of naming a ship for a person when the rule for that type of ship would have called for it to be named for something else. Some observers have perceived a breakdown in, or corruption of, the rules for naming Navy ships. Section 370 of the FY2021 NDAA (H.R. 6395/P.L. 116-283 of January 1, 2021) establishes a commission regarding the removal and renaming of certain assets of the Department of Defense (including ships) that commemorate the Confederate States of America or any person who served voluntarily with the Confederate States of America.
For ship types now being procured for the Navy, or recently procured for the Navy, naming rules can be summarized as follows:
The first and second SSBN-826 class ballistic missile submarines (SSBNs) have been named Columbia (in honor of the District of Columbia) and Wisconsin. The Navy has not stated the naming rule for this class of ships.
Until recently, Virginia (SSN-774) class attack submarines have generally been named for states, but the four most recently named Virginia-class boats have instead been named in honor of earlier U.S. Navy attack submarines.
Of the Navy’s 15 most recently named aircraft carriers, 10 have been named for past U.S. Presidents and 2 for Members of Congress.
Destroyers are being named for deceased members of the Navy, Marine Corps, and Coast Guard, including Secretaries of the Navy.
The first three FFG-62 class frigates have been named Constellation, Congress, and Chesapeake, in honor of three of the first six U.S. Navy ships authorized by Congress in 1794. The Navy has not stated the naming rule for this class of ships.
Littoral Combat Ships (LCSs) have been named for regionally important U.S. cities and communities.
Amphibious assault ships are being named for important battles in which U.S. Marines played a prominent part and for famous earlier U.S. Navy ships that were not named for battles.
San Antonio (LPD-17) class amphibious ships are being named for major U.S. cities and communities and cities and communities attacked on September 11, 2001.
John Lewis (TAO-205) class oilers are being named for people who fought for civil rights and human rights.
Expeditionary Fast Transports (EPFs) are being named for small U.S. cities.
Expeditionary Transport Docks (ESDs) and Expeditionary Sea Bases (ESBs) are being named for famous names or places of historical significance to U.S. Marines.
Navajo (TATS-6) class towing, salvage, and rescue ships are being named for prominent Native Americans or Native American tribes.