First good encryption is hard, and not something for us mere mortals to roll our selves. Linux Unifed Key Setup aka LUKS started as a way to standardize encryption key setup.
In on-disk-format.pdf states "The LUKS design can be used with any cipher or cipher mode." So as needs have changed ciphers can be changed.
Use Something Stronger?
from cryptsetup wiki FrequentlyAskedQuestions - Security Aspects.
Passphrase entropy Cost to break
50 bit EUR/USD 600k
55 bit EUR/USD 20M
60 bit EUR/USD 600M
65 bit EUR/USD 20B
70 bit EUR/USD 600B
75 bit EUR/USD 20T
Why not use LUKS2?
LUKS2 does not yet have a fixed API. See release notes for Cryptsetup 2.0.0 RC0.
From the release notse:
Release candidate with experimental features.
This version introduces a new on-disk LUKS2 format.
The legacy LUKS (referenced as LUKS1) will be fully supported
forever as well as a traditional and fully backward compatible format.
NOTE: This version changes soname of libcryptsetup library and increases major version for all public symbols.
Most of the old functions are fully backward compatible, so onlyrecompilation of programs should be needed.
Please note that authenticated disk encryption, noncryptographicdata integrity protection (dm-integrity), use of Argon2 >Password-Based Key Derivation Function and the LUKS2 on-disk format >itself are new features and can contain some bugs. Please do not use it without properly configured backup or in production systems.
Until final 2.0 version is released, the new API calls or LUKS2 format could still change if a major problem is found.