You can be forced to collect the data.

Bingo. And if the stakes were high enough many jurisdictions have laws that allow for it to happen under wraps. i.e. being forced to lie about collecting data.

I'm not sure it applies here?

Signal uses an OTR variant (I believe OTR masks the identity of the sender/receiver) -- not sure how thorough their implementation and protocol are[1]. Although if authorities already have the IP of one user they might gather a list of contacts.

[1] https://en.wikipedia.org/wiki/Signal_Protocol

But what makes you think they don't log ips. They could too. If whatever country they are based on ask them too

Metadata has been used to kill people.

The only way to avoid having your IP logged is for there not to be an organization that can be forced to log it.

So long as a company exists in a world controlled by US/European finance or is in their borders, they can be compelled to log what they are told to.

That's good though, no? They're collecting the information from you. I know it's a joke, but it's the difference between watching my home insides without me knowing - and showing up to my home with a warrant.

The joke is made at the expense of people who are naively saying that you can't be forced to turn over something you don't have, as if that's a defense that will work. They can mandate that you collect the thing they want you to turn over, then put you in prison and seize your assets if you don't comply.