Why is criticizing homosexuals considered a hate crime today, while loving a girl under 18 is considered a crime?

A friend of mine is dating a 16-year-old girl. He's 21, and their relationship is excellent. However, when people see this relationship, they consider it unnatural and pedophilic. I see it as a peaceful relationship. I've seen many in the LGBTQ+ community get angry about such relationships and see them as unhealthy. From my perspective, these homosexual relationships, which aren't part of human nature, are unhealthy. I'm not arguing in a derogatory way; I simply find it illogical. I know several people who were gay, and after their mental health improved, they left that community. I was also in a conversation with someone who became gay due to life pressures and problems.