Not just in Canada, it exists in the US too. They only offer US and Canadian numbers right now because of the partner carrier they use, but that “Proton SIM hub” is indeed an XMPP server. To make it even easier, they’ve also partnered with Snikket, and for the $5/month price of a phone number from JMP.chat, you can get a private dedicated personal XMPP server instance from Snikket. You’re free to do whatever you want with the Snikket XMPP instance (that’s XMPP related), and can create as many accounts as you want, and/or connect additional JMP.chat numbers to the same or different accounts on the server.
EDIT: They also take payment in Crypto or more traditional methods. It’s all prepaid flat-rate.
I dont know whether it was intentional from OP or not, but part of the issue with that is the connecting of your device network details to the SIM. In modern cellular networking, the KYC of your mobike plan is not at all necessary to completely deanonymize you. It sure doesn’t hurt to not have your carrier actively selling your personal KYC info already attached to your Messages, voice call info, and location, but it’s also in no way going to prevent it.