HomeKit has to be licensed for use in commercial products, and Apple puts a lot of restrictions on what you can do.
However, if you are not using it in a commercial product, you can use the HomeKit Accessory Protocol for free with very few limitations. This is what HomeKit Controller in Home Assistant is. Makes it act like an Apple hub, with the only two limitations being no access to iCloud and no Bluetooth HomeKit device support.
So if you load up Home Assistant, you can add many devices that Virtual Switches don’t cover, such as temp sensors, dimmers, etc. This makes them show up in Home Assistant as native device “entities”.
If a device has an entity in HA, then this App/Driver combination called Home Assistant Device Bridge, will bring them into Hubitat as if they were directly joined to your Hubitat Elevation hub. I use this myself, not for HomeKit devices at this point, but I am instead using it to bring Xiaomi devices into HE, since they are very stable with my ConBee 2 attached to HA, but tend to fall off the Zigbee network when joined directly to HE. It’s also very useful if you want to bring over a cloud integration that HA supports, but Hubitat is not compatible with at this time.