Yeah, in this case the only real issue is that tacking on 'made by ChatGPT' feels kinda weird. I feel like in society we like to keep up appearances and pretend like there's this level of special sincerity in those kinds of messages, but we all know that when we go to write them we're just copying ideas from other similar messages we see elsewhere and doing our best. It's rarely something truly personal, but it's a bit crass to pull back the curtain and show that.