Wait for executing a rule

Ye-es, sort of, kind of. But you need to manage your Timer, not create a new timer every key press, that is not helpful.

If you want to use timers, look at examples like window open alarms to get timer usage basics.

More sophisticated use

You probably want something in-between.
Let’s re-phrase previous workflow

When the user setting changes -
(a) cancel any existing timer
(b) start a timer for a few seconds ahead. But you must “remember” the timer in a global variable so that you can do (a)

When the timer expires, do whatever it is you do to send to device.

You’ll need to make a judgement about whether you need this to deal with multiple different group members changing at the same time, that will make it more difficult.