All “ketogenic” means in biochemistry, where the word comes from, is that the body utilizes fat for energy. The body has no idea what 20g of carbs are - that is our measurement for energy. 2-3 apple, tomato, or carrot slices are keto, in those amounts, and easily fit in macros. If we eat the whole pint of Halo Top, 2-3 tomatoes, and a whole apple, not so much. Many low carbers that eat 30-40g of carbs net (which winds up being 60-85g total depending) are easily still in ketosis, on the higher end even, especially if they are athletes. I regularly see people eating loads of “ketogenic” foods in big amounts, not batting an eyelash. If someone can fit this ice cream in, who cares?
One serving easily fits in keto macros, actually. While I’d never suggest you consume whole pints regularly, it’s keto in an appropriate amount. I can eat up to 65g a day of carbs and stay in ketosis (and did when I tested). For me, it easily works. For everyone? Not necessarily.
Making your own is always great! Working 80 hours a week didn’t leave me with much time to do it, and I only had ice cream once every 2-3 weeks if that, so for me, a pint of halo top was far easier, cheaper, and suited my schedule.