I would try a motion detector instead of location as a trigger.
If you would like more complex rules - combining motion with time of day or trying to also use location (such as gps or detecting your iphone by Wifi connection), you’ll probably need to have a smarter rules engine/hub than HomeKit/Google/Alexa such as Home Assistant or others. A fun project, but not something to tackle unless you enjoy the challenge and want to be able to do other advanced automations too.
I can see you’d maybe want it turn turn on for you, but nobody and nothing else, which precludes a simple motion detector, but I think a simple Bluetooth switch and timer might be your answer. Turn it on with your phone only when you need it.