Earlier quoted context omitted.
A category that includes both twinkies and whey protein powder doesn't seem that useful.
The rule of thumb is that the ultra-processed food should not account for a too large part of your diet. The protein powder is usually taken as a supplement and in small quantities, as opposed to food like twinkies people can easily overeat on. But try to make protein powder 80% of your protein intake and see how you'll feel in a week.
This is true for any food though. A different line of argument would be what if 95% of your protein came from whey and all other nutrients came from other sources. As long as you get the right balance of macronutrients and micronutrients i suspect you will be fine. Unfortunately studies on diet are very difficult to actually implement so we don't have the data to be certain.
Obviously most ultra processed food is low in nutrition, high in sugar, and high palateability so it makes sense that ultraprocessed foods are associated with bad health outcomes but I think it's a step too far to say that all ultra processed food is bad (it's probably a good rule of thumb for most people however).