I have repurposed a touch screen button on my Ultimate remote....but agree device mode can be confusing.....gave a Harmony to my brother's family and they would mix up activities and devices which can get weird....
The Ultimate was similar, but a different design WRT software and processing.
Either way, it's too easy to press the Device button and screw up the settings and I found out the hard way that the Denon AVR-3311CI would go WOT if its remote was in AMP mode and the number 1 button was pressed. That didn't make me happy, but it was their own remote and someone should have included that in the manual. If I had placed that command in an activity, I can't imagine the calls I would have received if the kids or babysitter had pressed it, expecting the AVR to do something different. If the homeowners had done it while hosting a party, yikes!
Universal remotes are supposed to minimize control problems but including a device button when someone doesn't have a list of settings for each activity is just asking for trouble.
I was a Beta tester for the Elite and the 2400 Pro hub- I tried to get them to eliminate the device button, but the program had been written and the hardware was in production. Fortunately, the first group call with their Digital Products Group and those of us who ended up being Beta testers was early enough that we could get them to change the 2.5mm IR jacks to 3.5mm, like everyone else.
I would like to go to Logitech HQ and kick someone's butt- they have the most comprehensive database, their tech support has been far more helpful that URC and their remote control sales were increasing by leaps and bounds but when COVID hit, everyone wanted to be able to do video calls to friends & family who couldn't be there and since those products require just about zero tech support and are very inexpensive to manufacture, it came down to money, not the users. Logitech sells more video conferencing hardware than anyone else in the consumer and even many pro markets. Sure, they'll support them for a long time- they sold far more remotes than their SlingBox which is still supported AFAIK, but that's not the point. I'm not sure they were actually aware of the shift from URC, RTi and a couple of other brands toward Harmony- even URC added a Help button to some of their models. The last time I went to a URC training session, they had nothing bad to say about Harmony, unlike several years before.