Very true :)
I had this exact issue with the Elgato StreamDeck user interface, which renders the macro buttons as one big canvas only drag-and-drop interacts with.
It's rare that I outright cannot figure out a way to make a UI accessible, but that one managed to break everything I tossed at it. I eventually switched my effforts to an open-source third party client which had a web UI, which is now accessible to screen reader users.
As for repairing HTML, my last few engagements have clearly shown me that while HTML CAN be repaired, many devs these days wouldn't know where to even begin to do that. The amount of hand-holding I've had to do has made me suggest, several times, to just give me git access as it'd be faster if I just fix it myself.