If you do ugly Pulldowns, pulling too low, rolling the shoulders forward and rounding over, dropping your chest, crunching up your shoulder joint, they are bad.
Its like “working” the impingment groove.
If you can keep your chest up, upper back arched, elbows under the bar and get great activation between your shoulder blades, they are good.
Its like rep after rep of anti-impingment groove.
If your shoulder is really painful, you might need to avoid vertical pulls for a little while, until there is no more acute pain. But I think skipping vertical pulls for too long is a mistake.
You may need to “special” handle (maybe close grip, or neutral, or underhand) at first, to get comfortable and “feel” your mid back. Or you might need to use a short ROM, or slow execution to keep the tension in the right place.