tl;dr check for desirable presence of argon2id as key derivation function in the output of

    lsblk
    sudo cryptsetup luksDump /dev/sd[xy]

or more terse (not sure if this works for luks1 header format too)

    sudo cryptsetup luksDump /dev/sd[xy] --dump-json-metadata | jq '.keyslots | .[].kdf.type'

if you see anything but argon2id, consider migrating. Thanks for the explanation and PSA @mjg59

https://anarchistnews.org/content/update-ivan-alocco has the english translation of the letter by comrade arsonist anarchist