I love this. I don’t know why the “agile board” became a thing. To me it always seemed like a poor way to visualize what is a list of items.
My problem with agile boards is that they place tasks into separate columns to denote the task state, which often cuts off the task description (and can require a lot of horizontal scrolling). It also prevents using columns for other fields like the Assignee (as the table view in the new GitHub Issues does).
I think the idea with boards is that the (artificial) constraints of the medium are helpful in certain team configurations. As far as I'm aware, boards are most strongly advocated in Kanban, where there's a hard limit on WIP -- so having a board where you actually cannot have more than 10 items in your backlog before everything goes to hell is a feature not a bug.
In Kanban, it's really important to be able to see at a glance, where your WIP is in the pipeline, e.g. you don't want to start a new task when there's a huge backlog of tasks waiting to be validated. In a table, you lose the ability to get a birds-eye view of the sprint status.
Most teams aren't doing Kanban though -- so I think it's plausible that most teams will find a table view more usable/efficient.