I think you need to learn more about open source, it's pure transparency, how can a project be open source and still have a backdoor? And no one sees the back door? What's the open source then?
Open-source projects have nothing to hide, you can easily see all their codes and what they are running, with no hide-and-seek like Closed source, what you just defined sounds exactly like Closed source projects.
open source is not about there being backdoors. as you can SEE the source code
but open source no longer means open community, open door involvement of the development and activation process of new features
by this i mean you can read the code, but that does not mean you can stop the code from activating now, if you see a fault or if that feature is not wanted by the wider community
2009-2014 new features required a deemed majority having the proposed code on their node ready, to then activate the feature without causing a fork.
now however, new features can be activated without the need of economic/wider community nodes/mining pool nodes being compliant and ready to validate the new rules.
it simply makes them outdated node just saying yes without checking the new rule. thus downgrading those nodes to less than full nodes requiring them to upgrade after activation to then know they are fully validating again and regaining full node status.
this lack of community involvement of development acceptance means that devs are not held to account or scrutinised by those outside their group. where we as the wider community have to trust their code that activates wont break bitcoin, and our only option becomes jumping over to an altcoin if things go bad
yes we can read the code. but we cannot then tell a dev that are pushing something bad into the activated ruleset
..
open source just means open to read. not open to review and critique and open involvement in acceptance or rejection of new lines of code
the saying now is
"if you dont like the code, fork off to altcoin and see who follows you"