I agree to a certain extent and I'm actively using Docker.
What I've done is made an Ubuntu VM, put Docker on it and booted a Portainer client container on it, then made that into a container template, so I can just give it an IP address and boot it up, then add it to Portainer in 3 clicks.
It's great for just having a go on something and seeing if I wanna pursue it.
But so far I've tried to boot and run Arr and Plex, and more recently Logitech Media Server and it's just been hard work.
I've found I'm making more VMs than I thought I would and just putting things together in them, rather than trying to run stacks of Docker together.
That said, it looks like it is awesome when you know what you're doing.
I'm currently running 3.5 inch HDDs via usb3.0 to sata. Working ok so far (time will tell) but I do need a plug socket for every one of them