Not disagreeing with anything else, but Linux is far from "modern".
Yes it is, try using a dictionary.
I tried that. After I'd finished stuffing it into my DVD drive (which was hard enough, I had to cut the corners off to make it fit), it just made ugly graunching noises, but wouldn't boot. Admittedly, I only managed to fit the first 200 pages in there (and I had to wad them up pretty damn tight to get that far) – maybe that's the problem.
So yeah, I'll grant you – Linux is a more capable and modern operating system than the first 200 pages of the Concise OED.
There are differences between a current Linux kernel and a 1970"s OS:
journaled file systems
object orientation (file-types and associations)
Access Control Lists
granular authorisation escalation.
And of course GUI
Yes, Linux has evolved from where it was when it came out, but it"s still, fundamentally, a clone of a clone of an operating system developed in the mid-60"s. The roots of Linux are 50 years old, and more. Everything you list above is a miniscule, incremental improvement on what came before. Unfortunately, the "incremental, don"t break any existing software, allow an upgrade path, don"t do anything radical" approach taken by the major OS players has hidden and / or stifled the real gems of OS development since the tail end of the "80s.
A parallel is the seemingly unstoppable rise of Microsoft"s "Excel" and "Word".
Far better and more capable spreadsheets than excel have existed (and, oddly enough, still do exist in a niche market), but the 800 pound gorilla of Excel means that even its competitors look, and behave, in exactly the same way that Excel does. Excel itself hasn"t noticeably improved since the introduction of pivot tables.
Word has been around since 1983, and it still can"t typeset for toffee (I was going to use another word referring to something that"s brown and sticky, but there might be kids watching). Typesetting is not a (very) dark art – Knuth"s TeX has been considered "stable" since the year the very first version of Word for Windows was released. And yet, we get clones of Word, complete with godawful typesetting.
Just because something is dominant, even if all its competitors are similar, doesn"t mean it"s the right way to do something.
In terms of modernity, Linux is no better than Windows or OSX. I"d argue that it"s trailing both of them.
As mole125 said:
Maybe we need to break away from our C and Posix heritage of writing operating systems … and accept that existing programs may need significant rewriting?
I agree, but I"d go even further. Existing programs need to go. Be thrown away. We need a whole new way of working. They are holding us back.
For example – "file systems", journaling or otherwise, are an abomination. Truly. Yes, we need somewhere to store files, but the file systems we have today are all hobbled by the idea of hierarchical storage – a kludgy workaround to deal with the fact we have no real metadata apart from file name and position in a some arbitrary tree. They are, by and large, tied to physical media – if you have 2 pieces of physical media attached to your machine, you have (at least) 2 separate filesystems. For the most part, they work extremely badly in a multi-user environment. The solution to this exists, and has existed for a very long time. But throwing away the file system as we know it means throwing *everything* away.
Somebody asked what I would consider to be a modern OS, if Linux isn"t it. There"s a few, and one of them is almost as old as Unix.
For starters, there"s NewtonOS. Fully object-oriented, extensible, data stored in a "soup" (object-oriented database, really) rather than in any hierarchical format, handled novel input methods, portable, and all running on a wimpy little ARM CPU, back in the dim and distant 1990s.
QNX, as rurwin mentions, has a far more modern core than any of the existing desktop solutions. The userland is pretty bog-stock new old stuff, though.
BeOS tried to do away with the file system, and managed to a fairly large extent. It probably counts as modern.
And then there"s the oldie. Genera / OpenGenera, which traces its roots back to the MIT CONS and CADR Lisp Machines from the early "70s. It"s totally modern. But, as you can probably guess, it doesn"t run Word.
There's a couple of other possibilities that spring to mind, too.
Windows "Longhorn" as originally envisaged might have made the cut, if only for the much hyped (and then cut) filesystem. Shame it turned into Vista, Win7 and Win8, really.
SqueakNOS looks interesting, but I don"t know much more about it than that.