Why Are My Photos Not in Order in Immich?
Immich sorts by the capture date inside the file. Takeout photos often have none. Here is the fix.
Immich builds its timeline from the capture date inside each file. When that is missing it falls back on the file date, which for a Takeout export is the day you unpacked it.
So the timeline collapses. Everything appears on one day, the year markers are meaningless, and the map is empty because the coordinates never made it into the photos either. Immich is not doing anything wrong; it is reading files that have nothing to read.
Fix the files before you import, and Immich indexes a correct library from the start. The app writes the real date and GPS into each photo as standard metadata, which is exactly what Immich expects. It can also write clean sidecars if you prefer that route. Fixing it after import means re-scanning everything, so this is worth doing in the right order. The first 500 photos are free.