ATF Improvement and Modernization Act of 2023 or the AIM Act of 2023 This bill removes limitations on the authority of the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) to conduct activities related to the administration of federal firearms laws. Specifically, the bill removes provisions that limit the use of firearms tracing data; prohibit consolidating or centralizing records maintained by federal firearm licensees, or FFLs (e.g., gun dealers); prohibit imposing a requirement that gun dealers conduct a physical inventory; require national instant criminal background check records to be destroyed within 24 hours; limit the disclosure of data under the Freedom of Information Act; prohibit the ATF from altering the definition of or denying certain import applications for a curio or relic firearm; prohibit the denial of a federal firearms license due to lack of business activity; prohibit transferring the ATF's functions, missions, or activities to other agencies or departments; prohibit the electronic retrieval of information gathered from firearm transaction records of FFLs that go out of business; and prohibit the ATF from denying an application to import certain shotguns. Additionally, the bill raises the liability standard for denying or revoking a federal firearms license from a willful violation to a knowing violation of federal firearms laws or regulations, and removes the de novo standard of judicial review for appealing the denial or revocation of a federal firearms license.