Generally, the further into the dungeon/adventure, the less direct the telegraphing needs to be to feel fair. I’m usually very overt the first time I telegraph something, and then get subtler and subtler with repeat instances of that thing.
If the players ignore it, that’s on them. That’s kind of the point, ideally you want it to feel like they could have avoided it, if they had been paying closer attention. That’s how you create that classic Dark Souls feeling of “hard but fair.”
I think that’s a great way to start a dungeon, as it tells the players exactly what they can expect to find - dart traps, leg-cutting traps, and kobolds. But I wouldn’t consider that sufficient to telegraph any individual trap. To do that, I would first of all want to add some detail that indicates the presence of each kind of trap, that the players might be able to pick up on if they pay close attention. For example, maybe the leg scythe traps are triggered when you step through a doorway, but only doors with brass handles. Maybe there are frescoes throughout the dungeon, and there are only dart traps in rooms where the frescoes depict someone with a missile weapon. That’s good dungeon design.