The theoretical benefits of Gentoo or Arch are completely negated by the fussy nature of those systems. You have more control, but to get it you have to do a lot more work. I’m not saying that’s a bad thing, just that’s the main difference between arch, gentoo, and a more streamlined distro.

Really it depends on what you want out of your distro. If total control is what you’re after, then gentoo is only the beginning of a deep k hole that ends in LFS and a ricing habit. Personally I like using my computer as a tool to do other stuff so anything more hands on than debian stable just gets on my nerves or turns me into a ricing addict. But I had to install gentoo to figure that out.

Gentoo is a filter. You either love it and continue diving or learn you want something else from your OS.

The point of use flags is to make it so if you don’t want to print, every package that would otherwise pull in CUPS as a dependency can be compiled without it. Stuff like that.

Gentoo also has a good system for handling multiple concurrent installs of different versions of some packages, e.g python.

If there’s software you want to install from source that uses automake it’s pretty simple to build your own package for it.

Very much a system for doing things your way, and a good way to learn linux IMO. To that end, no there is no installer, but the process is not that complex. Boot a live USB, partition and format a drive, download and extract a base system, install a kernel (there is a fits-most-needs one available now), install a bootloader. Reboot into your new system and continue installing what you need from there.

Frankly i found the Gentoo handbook much easier to follow then the arch wiki at the time I tried both. Just compiling everything takes a while to do.

The installer is the handbook.

USE flags are freakin’ awesome.

It can let you install two different versions of a library.

You can install the binary versions of some big packages like firefox.

Edit: while USE flags are generic, you can also set specific per-package flags.

There’s an old joke from a couple of decades ago about what operating systems would be like if they were airlines:

Linux Airlines

Disgruntled employees of all the other OS airlines decide to start their own airline. They build the planes, ticket counters, and pave the runways themselves. They charge a small fee to cover the cost of printing the ticket, but you can also download and print the ticket yourself. When you board the plane, you are given a seat, four bolts, a wrench and a copy of the seat-HOWTO.html. Once settled, the fully adjustable seat is very comfortable, the plane leaves and arrives on time without a single problem, the in-flight meal is wonderful. You try to tell customers of the other airlines about the great trip, but all they can say is, “You had to do what with the seat?”

Gentoo is still very much a “You had to do what with the seat?” distro, while most others have retired that concept to varying degrees, at the cost of the seats being less easy to perform unusual adjustments on.