Problem/Motivation
It looks like there is a missing condition on i18n_string.objectid in the d7_term_localized_translation source plugin.
As a result the first tid gets migrated correctly but all of the following tid (taxonomy terms) get the values from the first one.
Shouldn't we add: ->condition('i18n.objectid', $object_id);
in core/modules/taxonomy/src/Plugin/migrate/source/d7/TermLocalizedTranslation.php:73
Proposed resolution
The taxonomy term translation source plugin should use I18nQueryTrait properly. It is included but not actually used, as if it was intended to be used but was forgotten.
Remaining tasks
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