iPads not detected by PC, iTunes, or File Explorer

When your iPhones connect properly to your PC via File Explorer and Apple/iTunes apps, but your iPads charge only and fail to register, the issue is typically specific to the iPad OS trust state, distinct iPad-to-Windows drivers, or app handling. 

• Unlock the iPads: Ensure both iPads are unlocked with your passcode when plugging them in.
• Dismissed Trust Dialog: If you previously tapped "Don't Trust" or ignored the prompt, it will not appear again automatically.
• Reset Location & Privacy: On both iPads, go to Settings > General > Transfer or Reset iPad > Reset, and tap Reset Location & Privacy. Unplug and reconnect the iPad to force the "Trust This Computer?" prompt to reappear on the screen, then tap Trust and enter your passcode. 

2. Use the Apple Devices App Instead of iTunes (Windows)

• Apple has split Windows functionality, shifting management for modern iPadOS versions away from legacy iTunes over to the dedicated apple device app
• If you have both iTunes and Apple Devices installed simultaneously, they can conflict over device drivers. Uninstall legacy iTunes or use the standalone Apple devices app  to see if the iPads register properly. 

The split that WheelieNick mentions happened at Win 10. If your PC is running Windows 10 or 11, you should be using the Apple Devices app. Apple ref:

Use Apple Devices to share files between your Windows computer and your iPhone or iPad - Apple Support