Nowhere in my comment did I suggest that sticky keys simply shouldn’t exist.

Your post was this:

TIL about what sticky keys are for, but tbh in that case the person should really just use a programmable keyboard and map individual keys to those sequences.

Your post was one single sentence and I absolutely came away with the idea that you were suggesting that StickyKeys shouldn't exist because you found it a bother. With the responses from others I wasn't alone in my reading of your comment.

I was specifically responding to the OP talking about Ctrl-C/V and suggesting that a programmable keyboard would be a better solution for that, since you can turn 7 keystrokes into 1, since I expect that reducing the number of keystrokes one has to type is probably pretty valuable for someone in this situation.

I was pretty obviously talking about the normal case

It wasn't obvious at all.

You skipped three or four different steps to communicate to the audience about your intent. With your extra explanation, I see where you're coming from where you were focusing on solutioning for one specific example given for a use case of StickyKeys. However, your solutioning was too narrow in assuming the requirements included the disabled operator would only be using hardware they control 100%. There are many times that isn't the case, such as public computers at a public library, computers in a business center at a hotel, or various kiosk-based computers businesses use to collect input for scheduling or surveys. In those cases, the operator doesn't control the hardware at all.