All the info about TLP on the surface looks more like advertisement and marketing to me, I can't see any detailed comparison to default configurations. What are the precise differences compared to default (K/L)Ubuntu installs under the hood, are they really effective?
Update: And if they really are, why aren't they a part of a default config?
the difference of TLP's default config compared to a vanilla Ubuntu installation is quite simple:
The situation is different with other distros.
For even more aggressive settings you may use RUNTIME_PM_ALL=1 to enable runtime pm for all devices.
Additional gains are:
TLP's documentation contains only the facts about the settings, there is no advertising.
Taken from the ArchWiki, TLP provides optimized power saving by default (without altering its configuration files).
What it does by default (or you can make it do, I do not use it):
You can find the full list of its configuration options here, where it specifically says what it takes care of.