If a character casts Misty Step while in manacles (verbal only spell), what happens? Do they teleport with the manacles on? Or do they drop to the ground?
What if the character is chained to a wall?
If you can't move an object by normal means (pick it up and carry it), you shouldn't be able to bring it with you when teleporting. So if you're chained to a wall, you're in the clear: The chains don't go with you.
If you have manacles on, it's a more interesting question.
Dimension door states that you "can bring objects with you," implying that it's an optional choice; you don't
have to bring the objects. Thus you could leave the manacles behind. The question is, since
misty step has no similar language, does it work the same way?
On the grounds that the PC is expending a moderately valuable resource (a 2nd-level spell slot), for no other benefit than removing the manacles, I would rule that it works and you can choose to leave the manacles behind.
As for DMs saying "You didn't say you brought your gear with you, so you leave it behind," that's not a rules issue. That's a "you need a better class of DM" issue.