True Strike mechanically fails a significant portion of the time. It's a trap.
Indeed, and Find Traps wouldn't detect it because it wasn't intended to be so.
Find Traps only fails if no portion of the trap or trapped object is visible, or the DM is a d__k.
You act as though that is not a noteworthy drawback. Most spells work well even under whichever interpretation is the least useful, Find Traps does not.
If someone put a snake in a box with the intent to cause harm, I consider that a trap.
Sure, this is true, but that first half is significant. If it wasn't placed there specifically to cause harm (maybe someone didn't want it getting out, or maybe a critter just thought the box looked like a cozy place to rest, as opposed to "You know what would make a good trap? Something that requires me checking back pretty often to make sure it still has food, water, and air.") then Find Traps won't detect it.
If the ceiling can collapse, Find Trap detects that.
Not true, structural damage isn't always specifically intended by the structure's creator. I would go as far as to say it's usually not. In fact, the spell description even says, "[...]
but it would not reveal a natural weakness in the floor,
an unstable ceiling, or a hidden sinkhole."
If your party all look around thoroughly and everyone makes Perception/Investigation checks and can't find the trap, Find Traps won't help. You might say it can help you at least know if there's a trap in the area, consider this: If it says yes, it doesn't really help; if you cast Find Traps you had already suspected this was the case. If it says no, it still won't set you at ease because there are many conditions that cause something not to be detected. It's not that it fails that hard at finding traps, it's that it's just that unreliable. Sure, Find Traps can be useful sometimes, but every spell not named True Strike can be.