I can too, which is what gets me. Honestly after I think it might boil down to how far removed your provider is from directly getting the number from the FCC(or how trigger happy the entity they’re getting the number from). Also possibly if it’s considered a landline or mobile number, it looks like those are distributed differently.
I just saw one in fdroid and I can’t remember it now, lemme see if I can find it.
EDIT: it was zulip