Each app (formerly addon) can provide sensors for cpu and memory usage. Actually I believe it’s the Supervisor does that.
For some reason these sensors are disabled by default.
Is there an option to make them enabled by default for each new app?
Nope.
The Spook integration can enable entities. There also is a way to enumerate the integration entities for supervisor. I do not know if there is a way to enumerate entities that are not enabled though. If there is, you could combine the two. If there isn’t then it would come down to enumerating the devices for the supervisor integration, guess the ids from that and enable the ones you could not find.
But writing the code for it is a lot more work than clicking a few times per add-on that you install.