Is not wearing a belt with your dress pants considered “unprofessional”?

I was told that dress pants should fit close to your waist circumference, and that belts shouldn’t be used if followed properly. Even back then, they had at most waist adjusters on the side and belts weren’t an accessory often used when wearing suits. I personally never wear a belt with my dress pants as I try to buy pants that are my waist size only.

However, I often see upwards of 95% of men wearing belts with their dress pants. Is not wearing a belt considered unprofessional and looks sloppy? Thoughts?