You see this a lot in the auxlang movement that having gendered pronouns is sexist.
But making conlangs of my own, I find its absence to be often annoying. No one seems to realize how useful it is to be able to use different pronouns to refer to different people. If you only have one, you're often forced to just refer to everyone by name or some kind of title. I imagine in the real world, a true gender-neutral pronoun would eventually vanish due to its definition being too broad. At the very least its use would diminish over time even if it did exist, thus making it relatively temporary.