It's already established that we want Boost +python above (#29894)

var/spack/repos/builtin/packages/geant4/package.py

@@ -4,7 +4,6 @@
 # SPDX-License-Identifier: (Apache-2.0 OR MIT)
 
 from spack import *
-from spack.pkg.builtin.boost import Boost
 
 
 class Geant4(CMakePackage):
@@ -110,11 +109,6 @@ class Geant4(CMakePackage):
         depends_on('boost@1.70: +python cxxstd=' + std,
                    when='+python cxxstd=' + std)
 
-    # TODO: replace this with an explicit list of components of Boost,
-    # for instance depends_on('boost +filesystem')
-    # See https://github.com/spack/spack/pull/22303 for reference
-    depends_on(Boost.with_default_variants, when='+python')
-
     # Visualization driver dependencies
     depends_on("gl", when='+opengl')
     depends_on("glu", when='+opengl')