@Cenzorrll For comparison of LVM with BTRFS there are several article available.
https://www.baeldung.com/linux/btrfs-lvm
https://fedoramagazine.org/choose-between-btrfs-and-lvm-ext4/

From personal experience, I have an encrypted software RAID1 with mdadm and BTRFS on top.
Is not LVM, but same direction.
Before implementing this, I made some tests.
Related to encryption, when RAID1 was implemented with BTRFS, the CPU load had been doubled, because every BTRFS disk has an encryption process.
With software RAID1, only one encryption process is there.