Unless WWDC was already getting too long with all the software and Mac hardware, so there wasn't enough time at the event to also talk iPad hardware. In fact I see the iPad event as reasoning for why we might see Mac hardware, not the other way around - If there was only software on the programme, then there could be time enough to also talk iPad hardware, but that time is then taken over by Mac announcements.
But who knows. We have more software platforms than ever to go over as well.
macOS 15 (Redwood, please),
iOS 18/iPadOS 18,
visionOS 2,
watchOS 11,
tvOS 18,
All that could easily take up a fair bit of time, especially if the iOS 18 stuff is going to be pumped up as much as rumours suggest.