@adrian Thanks for your detailed answer. I went to the Hyundai garage today. And then straight to the BMW garage. The Ioniq 6 won hands down.
Specs – Ioniq 6. Eg. Electric seats. Adaptive cruise control.
Delivery date – Ioniq 6 (by a HUGE margin).
Boot space – Ioniq 6
Front seats space – Ioniq 6.
Back seat space – Ioniq 6.
Putting mother into the car from the wheelchair – i4 (JUST).
EV range – Ioniq 6.
@callmejohn has been telling me about the Ioniq 6. And I can confirm, no issues with the wheelchair.
I cancelled by i4 order and will be going on Monday to order the Ioniq 6.
Thanks to all who have helped by answering my questions and giving my advice.