I've been running the same containers for many years, changing hardware every few years. I started on OpenVZ, moved to linux-vserver, then to LXC, then to LXD ... then on my most recent hardware switch, back to LXD.

LXD's CLI-tool-driven configurations stored in sqlite might be nice if you're starting from scratch, but I gave up trying to determine the incantations required to port my stuff to it. It seemed like I couldn't use the CLI to get from here to there, but I was able to do so by directly modifying the sqlite database. When a CLI doesn't make all valid changes possible, that's frustrating at best. Going back to LXC took an afternoon and I have complete visibility over my configuration, because it's all simple text files.

LXD feels like it's at a point between LXC and K8s, but I'm not sure how many real-world systems want to be there.