I don't think our views are so incompatible, I just think there are two conflictual paradigms supporting a false dichotomy: one that's prevalent in the business world where "cost of labour shrinks cost of hardware" and where it's acceptable to trade some (= a lot of) efficiency for convenience/saving manhours. But this is the "self-hosted" community, where people are running things on their own hardware, often in their own house, paying the high price of inefficiency very directly (electricity costs, less living space, more heat/noise, etc).

And docker is absolutely fine and relevant in this space, but only when "done right", i.e. when containers are not just spun up as isolated black boxes, but carefully organized as to avoid overlapping services and resources wastage, in which case managing containers ends-up requiring more effort, not less.

But this is absolutely not what you suggest. What you suggest would have a much greater wastage impact than "few percent of cpu usage or a little bit of ram", because essentially you propose for every container to ship its own web server, application server, database, etc… We are no longer talking "few percent" of overhead of the container stack, we are talking "whole new machines" software and compute requirements.

So, in short, I don't think there's a very large overlap between the business world throwing money at their problems and the self-hosting community, and so the behaviours are different (there's more than one way to use containers, and my observation is that it goes very differently in either). I'm also not hostile to containers in general, but they cannot be recommended in good faith to self-hosters as a solution that is both efficient and convenient (you must pick one).