iPhone receives SMS from Info I am receiving an SMS from Info on an iPhone running iOS 13. There is no contact Info in my address book. Does this perhaps mean that the sender suppresses her address/telephone number? Or what else can cause this?

UPDATE I should clarify that the exact scenario is as follows: I'm sending an SMS to a phone number; for what I know there is a person at the other end. A few minutes later the response arrives from Info (e.g. hence the iOS Messages app shows it in a new thread, which is somewhat inconvenient.)
Since your device didn’t assign the name, it came from caller ID 

Contact your carrier for details of how and why they vet those names or if they just let people feed data claiming to be whatever sender they want and easily spoof (Lie to) the caller ID system. 

Your carrier and national cell phone regulator would be the people to look at if and how SMS naming is being regulated or if the carriers can do whatever they please in terms of naming and whether you get to know who sent that SMS.