Yes, he does seem to be storing character entries in SRAM then mapping them into a series out output bytes via an LUT, but VGA itself is still very much an analogue interface. It takes to top line of all of the characters in the top row before moving down to the second row and so on. I don't know off the top of my head what interfaces e-paper screens take, but I suspect they're digital, but probably expect a bitmap to display. Otherwise they'd need to support something like postscript (which we used to use to make printers layout pages like we wanted, using ASCII plus control sequences), and I might be behind the times, but I still class a postscript implementation as being quite a heavyweight kind of a thing (but then I remember having to upgrade printers with whopping - count 'em - 4MB RAM sticks to make them work better).
The thing you're thinking of is serial comms to old terminals like DECs VT220 series - that's ASCII+ANSI control codes, and kind of depends on a monospaced font, which you don't want on an e-paper screen normally.