Also, there is some talking on github on how they will probably completely drop LVM in the near futur… That’s not what someone should expect from a Linux installer!

It’s a shitshow. Looking at their repo’s issues list has lots of noise, but the worst of them is that the LVM issue has been open for over a year now. Sure, open source, anyone’s free to work on it by why would distros use such a feature incomplete installer?

Even then those who have to installers don’t really have a good experience with distros of wide market share (narrowing to Linux distros only), especially with whatever fresh hell Calamares is. (It doesn’t even support LVM or just installation with specified mounts points if you already set up your partition layout!)
Seriously, I’ve had better experience with the installer Ubuntu Server uses.