The argument isn't that a workaround doesn't exist, but that it wasn't a good trade-off, given the practicality of the 3.5mm port. Sure, I can easily use that adapter... even leave it attached to my ear-buds cord, etc. Or, I can remember to bring it along, so I can plug it into the car audio system when I go for a drive.
But, it isn't, IMO, an equivalent port. I very often have the device in my pocket with wired ear-buds plugged in, so I can listen to podcasts, etc. while I work in the yard or around the house. Others put it in their backpack or elsewhere while they listen. The problem with this is that there's a pretty big mechanical difference between a 3.5mm and Lightening.
When a 3.5mm jack gets stressed (especially over and over), typically it fails where the cord bends. When a Lightening connector gets stressed, it may very well do damage to the connector or port on the device. I don't know how much it costs to replace the Lightening connector, but I'd rather not find out.