I think we need to require ^3.6.0 because older versions don't support PHPUnit 10+ in their test cases (that's the reason for all the failures about missing arguments, as PHPUnit 11 does not support @dataProvider annotations anymore).

and for the test failing for TranslatableInterface in the global parameters, I think it might be a legitimate reason to use 3.6.1 as lowest bound to have that fix available: symfony/translation-contracts@3a74934
But this means we need to release that fix.

I had a deeper look. For PHPUnit 12 compatibility we need #58182 (released in 3.6.0). For the then remaining test failure we need #61111 which isn't released yet.

Ah, OK, we need #61111 on 8.0