How do you deal with relatives buying junk/stuff you don’t want or need?

I don’t mean to sound ungrateful or bratty but I’m trying to set clear guidelines with my close family. They are all really excited to shop for the baby which is a blessing but a few things have come up where I’ve specifically asked my sibling not to get clothing with weird sayings on it like things that are really engendered or stuff that says like “ladykiller” for boys or “daddy’s little nightmare” for girls. I just think it’s cringey and inappropriate. To this they responded “just because you don’t like it doesn’t mean the baby won’t like it”. Am I the asshole for setting this boundary? Additionally, other family members are garage sale fiends. Which I think is great but there are some items for the baby I would not like to be secondhand for safety reasons and I don’t know how to say this politely. Any advice?