Can a non apple user access my home pod mini

Actually Siri on HomePod should generally respond to any request made of it, but personal requests require that it identifies who is speaking. See Make Personal Requests on HomePod - Apple Support. Anybody in range should be able to ask it the time, or the weather, or to play some music. What music it can play will depend on the default music account it is signed into.

It is also possible to allow AirPlay from anyone in range of the HomePod, with or without a passcode, or anyone granted access to your Wi-Fi network.

tt2

No. You need an Apple ID and Apple device.

HomePod User Guide – Apple Support (AU)

Access what exactly? Assuming you have your HomePod set to everyone - any person within range can talk to SIRI and make music requests, etc.