You could run it in an emulator.

do you mean literally 10.6 on AS or do you mean something as good as it was

Something that good.

It was coherent, (relatively) bug free, and lacked the idiot level iOSification and nagging that is creeping in all over MacOS today.

I haven't had to restart Finder until recently, but now even that has trouble with things like network drives.

I'm positive there are many internals today that are far better than in Snow Leopard, but it's outweighed by user visible problems.

It shouldn't surprise you I think that Android Jelly Bean was the best phone OS ever made as well, and they went completely in the wrong direction after that.

It was very easy to lose data in Snow Leopard because they hadn't introduced the document autosave system yet. That was the next version.

You mean it only did things you told it to do? That's a feature.

Programs absolutely could have much more controllable auto save before for when it made sense.

"I lose work when the power goes out" is not a feature. Neither is "I can't apply security updates because I can't restart".

Speaking of security it didn't have app sandboxing either.

You mean programs could access the file system normally? They were absolutely isolated as standard unix processes.

This is what I mean about iOSification - it's trending towards being a non serious OS. Linux gets more attractive by the day, and it really is the absence of proper support of hardware in the class of the M series that prevents a critical mass of devs jumping ship.

The only Unix security boundary is between users. There isn't a standard boundary between "a web browser tab" and "the file with your credit card info in it".

The SL GUI enhancements live with us to this day.

last solid MacOS IMO