Database
[{"_id":"1","prices":{"2024-01-01 00:00:00":"11","2024-01-02 00:00:00":"22","2024-01-03 00:00:00":"33"}},{"_id":"2","prices":{"2024-01-03 00:00:00":"33","2024-01-04 00:00:00":"44","2024-01-05 00:00:00":"55"}}]
Query
db.collection.update({},[{$set:{prices:{"$arrayToObject":{$filter:{input:{$objectToArray:"$prices"},cond:{$gt:[{$toDate:"$$this.k"},ISODate("2024-01-01T00:00:00Z")]}}}}}}],{multi:true})