Why Do You Need a SIM Card to Create a Wi-Fi Hotspot on Your Phone?

Basically, a hotspot functions by sharing internet from a cell network. If there's no SIM card, there's no way for your phone to connect to that network, and thus no hotspot can be created.

You might have a bit of a misconception about how Mobile Hotspot works. It uses your mobile data to create a Wi-Fi network for other devices. No SIM card means no mobile data, so you can't set up a hotspot with just Wi-Fi.

A Wi-Fi hotspot lets other devices share your cellular connection over Wi-Fi. To make that work, you need a SIM card (or eSIM) since it provides the cellular connection you'll be sharing. Without the SIM, there's no cellular data to share.

Most of the time, Wi-Fi hotspots rely on cellular data for internet access. If you want to share an existing Wi-Fi connection your phone has, you'll usually need to do it via Bluetooth or USB, not through a traditional hotspot.