Yes. How many worst generation pirates are using haki? Luffy, Zoro, Law... and that's it. I never heard it being a requirement. I heard it was for those who trained their senses hard enough to acquire it. Usopp got his because he focused on survival with his pinpoint range for 2 years. That unlocked his Kenbunshoku Haki. His sense of his surroundings from close to extremely far has become so powerful due from training 2 years.
someone like bellamy has haki, and he got one-shotted by luffy. haki wasn't stated to be a requirement, but it has certainly become the norm to have now, especially in the new world.