Can no longer stream Apple TV or HULU etc, from iPad or iPhone

Are you trying to use AirPlay, or through an HDMI adapter, or watching on mobile directly?

For AirPlay:

To what device are you trying to AirPlay? Is it listed as an AirPlay-enabled device? Do you have an Apple TV box, or something else? Not all devices that support the Apple TV app also support AirPlay. These are independent features.

Use AirPlay to stream video or mirror the screen of your iPhone, iPad, or iPod touch - Apple Support

If screen mirroring or streaming isn't working on your AirPlay-compatible device - Apple Support

AirPlay system requirements - Apple Support

List of AirPlay-enabled TVs and third party streaming devices - Apple

Note that AirPlay is a different protocol from e.g. Chromecast or Miracast.

Verify that AirPlay is activated on the receiving device.

Verify that the content provider supports AirPlay for their content. Some do not. Some may have minimum system requirements for the receiving device. See their respective websites. What type of content were you trying to stream?

Hulu says to support AirPlay to Apple TV box (3rd generation or later). I expect the same for Apple TV+ or iTunes Store movies.

Apple lightning connector to an HDMI cable to the TV

Thank you for that detail. Unfortunately I do not have this adapter to try myself.

The adapter would support mirroring for apps/content that allow mirroring. Some apps may choose to block mirroring, and can change their behavior at any time, e.g. through app updates.

Try a restart of the iPhone or iPad.

Try force-quitting and relaunching the apps used.

Else please consult with Hulu Support and Apple Support for their policies on mirroring through an HDMI adapter from iPad or iPhone for the type of content that failed for you.

Else consult with Apple Support about the reduced functionality of your adapter.