It kind of makes sense. App delivery is notorious for being pretty terrible service quality and having the food end up worse with more time spent between kitchen and you eating it. Pizza delivery on the other hand has been seen as quick with drivers interested in earning their tip, pizza places being conservative with delivery radius to not overextend their drivers, etc. Customers don't like getting an inferior product or service one day.
Additionally, at least in my experience it's pretty easy to get to where just paying the delivery fee of a pizza place is cheaper than paying for inflated per-item rates.
They're saying that the space these companies are competing in literally did not exist. It didn't in the US, maybe not 15 years ago, but 20 years ago it was nonexistent.