What do you mean? In 20 years they changed the laptop power adapter twice and the iPod/phone adapter once. iPad is the worst (2 in ~8 years) since it arrived late in the ipod connector life and adopted usb-c early. In iPad's case it aligned with similarly positioned products and was generally a good upgrade.

Compare to other laptops which never had a standard adapter, phones which were also not standard until they moved 3 times in ~8-10 years from barrel jacks to mini-usb to micro-usb and now usb-c.

I don't have a source but owned MBPs and Airs from the first up until USB-C, and I had more than 3 different power adapters including USB-C for them. But you may be right and I remember differently.

But I might confuse those with display adapters.