Elder Justice Reauthorization and Modernization Act of 2021 This bill reauthorizes, provides funding through FY2025 for, and otherwise makes changes to, programs for preventing, detecting, and treating abuse, neglect, and exploitation of older adults. Specifically, the bill provides funding for states and localities to enhance adult protective services and long-term care ombudsman programs. Additionally, the bill modifies an existing long-term care workforce grant program, including by requiring that grant recipients use funds to provide employees with wage subsidies, educational assistance, and access to affordable child care and transportation. Furthermore, the bill establishes new grant programs for states to (1) link health care and social services for older adults, including through medical-legal partnerships and legal services hotlines; and (2) prevent and address social isolation among older adults and individuals with disabilities. The bill also provides funding for reporting by the Department of Health and Human Services on the effectiveness of various programs and activities in addressing abuse, neglect, and exploitation of older adults.