No it's not harsh. You're trying to do something nice and it's not being appreciated

I think they’re odd to act this way. Even if you bought all kinds of football stuff for him, he may never like the sport. But it’s lovely that you do it to share your love for football

Youre right to limit gifts to birthdays and xmas in this situation

Mom might lighten up about the situation when the kid gets older when she realizes she cannot control everything

Sounds like the baby's parent(s) are a-holes...but what do I know? Ignore their stupidity and pray it isn't passed on to the baby.