Why Are My Photos in Random Order?
They are not random. They are sorted by a date that is missing from most of them, so the fallback dates decide the order.
The order is never random. Your app is sorting by a date, and for many of the photos that date is missing. It uses the file date instead, which is when the file arrived, so those photos clump together wherever that puts them.
The result looks shuffled because two different kinds of date are mixed in one list: real shutter times for some photos, arrival times for the rest.
Give every photo a real date and the order settles down. Takeout JSON Metadata Fixer fills in the missing ones from your Takeout export. It runs on your own computer and is free for your first 500 photos.