I'm struck by how much this sounds like a Linux fan ranting back in 1995, when Windows and "real" UNIX was king. The underdog rants were rampant back then (I'm sure I penned a few of them myself).

I think the assumption you're making is that people choose Linux out of ignorance (and, I think the ignorance goes both ways; folks using Solaris have been so accustomed to Zones, ZFS, and dtrace being the unique characteristic of Solaris for so long that they aren't aware of Linux' progress in all of those areas). But, there are folks who know Solaris (and its children) who still choose Linux based on its merits. We support zones in our products/projects (because Sun paid for the support, and Joyent supported us in making Solaris-related enhancements), and until a few years ago it was, hands-down, the best container technology going.

Linux has a reasonable container story now; the fact that you don't like how some people are using it (I think Docker is a mess, and I assume you agree) doesn't mean Linux doesn't have the technology for doing it well built in. LXC can be used extremely similarly to Zones, and there's a wide variety of tools out there to make it easy to manage (I work on a GUI that treats Zones and LXC very similarly, and you can do roughly the same things in the same ways).

"Are you kidding me? System V is great, it's grep -R and tar -z that I hate, because it only works on GNU! Horrid!!!"

Are you really complaining about being able to gzip and tar something in one command? Is that a thing that's actually happening in this conversation?

I'll just say I've never sat down at a production Sun system that didn't already have the GNU utilities installed by some prior administrator. It's been a while since I've sat down at a Sun system, but it was standard practice in the 90s to install GNU from the get go. Free compiler that worked on every OS and for building everything? Hell yes. Better grep? Sure, bring it. People went out of their way to install GNU because it was better than the system standard, and because it opened doors to a whole world of free, source-available, software.

"You do realize that if you take an illumos derived OS like SmartOS and Linux, and run the same workload on the same cheap intel hardware, SmartOS is usually going to be faster"

Citation needed. Some workloads will be faster on SmartOS. Others will be faster on Linux. Given that almost everything is developed and deployed on Linux first and most frequently, I wouldn't be surprised to see Linux perform better in the majority of cases; but, I doubt it's more than a few percent difference in any common case. The cost of having or training staff to handle two operating systems (because you're going to have to have some Linux boxes, no matter what) probably outweighs buying an extra server or two.

"and if you are virtualizing, more efficient too, because it uses zones, right? Right?"

Citation needed, again. Zones are great. I like Zones a lot. But, Linux has containers; LXC is not virtualization, it is a container, just like Zones. Zones has some smarts for interacting with ZFS filesystems and that's cool and all, but a lot of the same capabilities exist with LVS and LXC.

I feel like you're arguing against a straw man in a lot of cases here.

Why do you believe LXC (or other namespace-based containers on Linux) are inherently inefficient, compared to Zones, which uses a very similar technique to implement?

And, it's not Linux' fault the systems you manage are stuck on ext4. There are other filesystems for Linux; XFS+LVM is great. A little more complex to manage than ZFS, but not by a horrifying amount. So, you have to read two manpages instead of one. Not a big deal. And, there's valid reasons the volume management and filesystem features are kept independent in the kernel (I dunno if you remember the discussions about ZFS inclusion in Linux; separate VM and FS was a decision made many years ago, based on a lot of discussion). Almost any filesystem on Linux has LVM, so, filesystems on Linux get snapshots and tons of other features practically for free. That's pretty neat.

Anyway, I think SmartOS is cool. I tinker with it every now and then, and have even considered doing something serious with it. But, I just don't find it compellingly superior to Linux. Certainly not enough to give up all of the benefits Linux provides that SmartOS does not (better package management, vast ecosystem and community, better userland even now, vastly better hardware support even on servers, etc.).