...it is still worrying if in community projects such as Debian when decisions that come with a cost to some part of the community are pushed through without full consensus.

What are some concrete cases you can point to where a decision was made with full consensus? Literally everyone agreed? All the users?

I'm not sure many projects have ever been run that way. I'm sure we've all heard of the Benevolent Dictator for Life (BDfL). I'm sure Linus has made an executive decision once in a while.