Does Time Machine also restore files from older backups not present in newer ones?

Doing a full restore from Time Machine will restore exactly one snapshot (usually the most recent one), without any files/folders only available in other/older versions. Which actually kind of makes sense if you consider that TM also backups OS files etc where you don't what to have a flattening effect with files from previous versions.

You can recover files only available in older snapshots through the Time Machine interface from Finder though.