opam remove ignores $OPAMAUTOREMOVE

[pirbo]

# opam config report
# opam-version      2.0.5 
# self-upgrade      no
# system            arch=x86_64 os=linux os-distribution=debian os-version=10
# solver            builtin-mccs+glpk
# install-criteria  -removed,-count[version-lag,request],-count[version-lag,changed],-changed
# upgrade-criteria  -removed,-count[version-lag,solution],-new
# jobs              7
# repositories      1 (http), 3 (version-controlled) (default repo at eaaaab1a)
# pinned            0
# current-switch    4.09.1+flambda

In a fresh switch, I opam install --unset-root re
But then

$ OPAMAUTOREMOVE=yes opam remove
Nothing to do.

whereas

$ opam remove -a
The following actions will be performed:
  ⊘ remove re   1.9.0
  ⊘ remove seq  base
  ⊘ remove dune 2.5.1
===== ⊘ 3 =====
Do you want to continue? [Y/n] 

[rjbou]

From a bisect, seems that it is not handled since 5 years :D
Thanks for the report!