The suggestion
"It's already hard enough to get people to respect humans, let alone animals. Let's fight for humans first and leave animals for later."
Problem 1: putting it off is a terrible strategy
If it's hard to get people to respect animals, that's a reason to start now, not to wait. Changing how people think takes time.
Problem 2: one doesn't block the other
The suggestion assumes nobody can respect animals while other people still disrespect humans. That's false. Each person can change their own behavior right now. And each person makes a real difference for the animals affected by their choices.
A comparison
Imagine someone saying: "Let's stop standing up for women and children until all adult men are respected; that's the best way to get respect for women and children." Everyone would see that this makes no sense and that the suggestion undervalues women and children.
The suggestion to leave animals for later can be, deep down, a form of hidden speciesism.
In short
- If it's hard to change people, it's better to start now.
- Respecting animals doesn't depend on everyone already respecting humans.
- Leaving animals "for later" can be hidden speciesism.