On the one hand I love single-focus nicely designed hardware. On the other hand I have a https://getfocustimer.com/ gathering dust, because a timer is just easier to set from the computer + screen I am already looking at...
Yes, my experience as well. That's why having an alternate small display (8" or smaller) for your laptop/desktop is better. You can then drag any application on it and use it as a timer or busy sign or whatever. It's way more convenient than an extra device you have to reach and fiddle with.
The only product in this category I still use on the regular is https://boomkat.com/products/buddha-machine-special-edition-... and its predecessors.