I grew up in the 80's programming my C64, assuming that this would be more or less the sort of thing I'd be doing for a living. The reality is actually pretty disappointing. I _wish_ anybody still did this stuff.
I wrote something similar in the 1990s. Except, I had to write the TUI library myself (in x86 assembler) since nothing like what I needed existed at the time.
I was working on a project to do ECU performance curve remapping for a rally driver friend, so mine had additional features like the ability to export memory segments as .m files for plotting curves in Matlab.
I watched a video about ECU remapping (on a modern processor) yesterday, and the guy started by using the OBD port to get access to the system. I had to physically desolder the EPROM from the board to dump it back in the day.