SharePoint "Alert me" feature: Does not support sending alert for specific column value
Rules in SharePoint lists: Supports sending alert for specific column value. Alert will be sent immediately, does not support sending daily/weekly summary like alert me feature
Power automate flow: You can run a scheduled power automate flow (daily/as per your requirements), which will capture the items changed to "True" and modified for current date and send email notification - This gives you flexibility to use custom email body for notification.
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