I have a C8 Pro. I upgrade to 2.4 Hubitat. I have a Webcore piston that uses a Hue Runlesswire button to turn on a non Hue outlet. Before 2.4 I had the community advanced app and picked that switch to have a higher poll rate to make this work. It was meh, but worked.
Once I got 2.4, I got rid of the advanced hue app. I clicked the button in the Hue App to use the push API. I fixed my piston. Wow! Was it responsive.
The other day everything was running slow, and that switch would not respond. Other automations in Webcore, and voice, were running slow.
So I rebooted.
Things are fast again.
I went into the logs and saw a high usage from the Hue App. Is this a problem? I didn't custom tweak the app. I just took the defaults (beyond upgrading to hues latest push API)
I don't think so: 81.6% of 2.5% isn't much all considered. But if you wanted to try anything: the app will wake for polling, most of the time when an event comes in from the bridge, when a command is sent, and when the app UI is used. Among those, the polling interval is probably the easiest for you to control. The default is 1 minute, but with the V2 API (you must be using that if you have button devices), you could reduce it to every few minutes or longer if you wanted. Most events aside from certain color events and ones missed to due an occasional error with cut-off data from the Bridge should come through instantly (one reason I don't recommend entirely disabling it).
Note that Hubitat platform versions have four sets of numbers, and while all are important, the first three are the most important: 2.4.0 is the current major version (there will be a 2.4.1 as the next major version, and so on, so "2.4" isn't enough), and 2.4.0.146 is the latest build, which I would recommend if you are not already on it.
