No, it’s not a scam. I have received a series of emails about the shutdown of Photo Stream. If you are using iCloud Photos, the shutdown of Photo Stream has no bearing at all on your situation. You are fine.
Even if you are using Photo Stream, you will not lose any photos. The photos will be saved on the device that took the photos. IOW, if you took photos on your phone and they appeared in the Photo Stream on your iPad, unless you save the photos in the Photo Stream on your iPad, they will disappear from the iPad when photo stream shuts down. However, the photos will still be saved on your phone.
This might help you understand it better.
Information about the My Photo Stream shutdown - Apple Support