Thread/Matter won’t require hubs. And, I’m guessing iPads don’t include Thread Border Routers.
Thread devices connect to the rest of your home network (and subsequently, the internet) through what’s called a Thread Border Router, which is a device that acts as a bridge between the Thread network and your home WiFi network. Unlike other bridges and hubs, though, Thread Border Routers can be built into other devices. The following products will, or are likely to, act as Matter-compatible Thread Border Routers: Amazon Echo (4th gen.) smart speakers; Apple HomePod Mini smart speakers; Apple TV 4K (2021) streaming devices; all Eero Beacon, Eero Pro, Eero Pro 6, and Eero 6 mesh WiFi routers; Google Nest Hub Max smart displays; Google Nest Hub (2nd gen.) smart displays; Google Nest WiFi routers; and all Nanoleaf Elements, Lines, and Shapes lighting products.