👋 sorry for this late reply, but this piqued my interest when I saw it in the email roundup for this group.
We had the same problem in my last place and we also opted for the env per folder approach. In the end, what we really wanted was automated progressive delivery from one environment to the next. So that changes flowed automatically all the way to production.
We ultimately ended up building this promotion automation to copy e.g. image versions defined in one env folder to the next, based on a progression through our environment phases (staging, pre-prod, prod and so on). This promotion automation actually opened up PRs to propose the change, but automatically put those PRs into a merge queue, so no one had to be around to merge them.
My experience working on that stuff has fed into a little experiment project we’re doing now called
cup. Cup doesn’t do the promotion bit (yet at-least), but it helps to create an API over Git that when you request the repo to be in a new desired state, they automatically become PRs. A step towards making that kind of automation easier to develop.