When selecting a TB, the options are either going language by language or choosing one for all languages. If one chooses All, then they can't select a TB whose languages don't all perfectly match the projects.
When selecting a TB, the user can select one whose languages don't all perfectly match the projects, as it used to work before.
If a TB only has a few of the project languages, it can no longer be selected for that project, unless the user selects it manually for every language. Plus, this also requires the user to check beforehand whether their TB languages all perfectly match the project ones.