So there are two reasons, one is scratching the paper, and the other is that the ink dries too slowly.
There are also two solutions. One is to grind the nib, with ordinary paper or sharpening oil stone or girls with nail polish, sanding the nib to use that surface, so that the tiny metal burrs are ground off. Most new pens need to be baked to remove wax and then sanded before they can be used.
The second is to use quick-drying ink.
Drawing a stroke and then having to dip it in water again rarely bothers anyone, so no one has considered any solutions. It's better to stop with one stroke and have a time and rhythm to reflect on the picture and the line than to draw continuously.
Because of the above reasons, there is little demand for water-reservoir nibs. The country mainly purchased domestic Lighthouse reservoir nibs, which were inexpensive, and the craftsmanship and design were (at the time) world-class. However, because of the low demand for such nibs, they have been discontinued for a long time, and they are all 20 or 30 years old. Many of the nibs in the Lighthouse series are reservoir nibs, such as the 801,824,126,426.
What's "black ink for colorful people"? ...... Never heard of this brand.