> You can use a trademark any time you want.
No, you can't. If you could use it whenever yoh want, we wouldnt have the concept of “nominative fair use” as the exceptional case of when and how you are allowed to use someone else’s mark in commerce without permission.
Mmm. “Anything” is maybe hyperbole.
You can’t represent yourself or product as a brand. But you can write a scathing review about them and use their name and nobody can stop you. That wouldn’t be a trademark situation, it would be defamation, not infringement.