Type signature of @property not shown in help()

GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2019-12-23.15:40:00.651>
labels = ['type-feature', '3.9', 'docs']
title = 'Type signature of @property not shown in help()'
updated_at = <Date 2021-04-11.00:19:47.157>
user = 'https://github.com/McSinyx'

bugs.python.org fields:

activity = <Date 2021-04-11.00:19:47.157>
actor = 'rhettinger'
assignee = 'docs@python'
closed = False
closed_date = None
closer = None
components = ['Documentation']
creation = <Date 2019-12-23.15:40:00.651>
creator = 'McSinyx'
dependencies = []
files = []
hgrepos = []
issue_num = 39125
keywords = []
message_count = 5.0
messages = ['358823', '358825', '359041', '390625', '390754']
nosy_count = 5.0
nosy_names = ['rhettinger', 'docs@python', 'McSinyx', 'xtreak', 'brenthuisman']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'enhancement'
url = 'https://bugs.python.org/issue39125'
versions = ['Python 3.9']