This is an even more myopic view, than the ones I have come across before e.g. why do I need a Harmony, my X device already comes with one?

I certainly did not need one, until the remote for my Yamaha amp (circa 2005) gave up on me, which in itself had basic functionality to be programmed as a universal remote. I could not find a direct replacement, tried fixing it, and then managed to find someone in Yamaha (Sound & Vision) willing to have a look at it, who subsequently declared it officially dead.

After having a look for alternatives, I bought the Harmony 700, which ended up controlling all my devices from the Amplifier to Xbox. Unfortunately, that gave up too -- it is fixable, but for now it sits in the box of projects to do. I briefly used the Samsung Galaxy S4 which has an IR emitter, to plug the gap, but it was extremely slow. I then bought the Harmony Touch, which I am still using today.

To answer your question, it is not entirely unimaginable that there are older devices which serve their purpose, but do not have 'smart' functions, yet they still require IR to be operated/controlled. For example, I lost/misplaced my old Apple TV and FireTV remotes ─ it was quick and painless to program them into the Harmony. Although the latter has a good app, but nothing beats a tactile remote without latency, especially if it is programmable and offers a single-press, multi operation features.

There are people like me, who would not want the Harmony to die -- which it probably will eventually, as Logitech won't continue to provide support for a product, they no longer sell. It will be even quicker, if people refuse to see the use cases, and keep questioning its existence.