Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
AFAIK, the downgrade option is no longer available. If you want to completely avoid the subscription cost and AI features , you'd need to cancel your 365 plan and purchase a lifetime license for a standalone desktop suite like Office Home https://www.microsoft.com/en-us/microsoft-365/p/office-home-2024/cfq7ttc0pqvj.
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hth
Marcin