What do you fine folks think? I'll go first.
 
For PC:
 
Best of all time: Tie (Cheating I know) Fallout-New Vegas and Skyrim
 
Best in Last 5 Years: Red Dead Redemption 2
 
Other System:
Best All Time and Last 5 Years: Zelda - BTOW (far and away the best)

You really enjoyed State of Decay 2? I really tried playing it, and getting into it, even trying to play with a friend but it got super repetitive, "another settlement needs help" got tedious with resource grinding and I felt I had no direction. I understand that there are multiple campaign goals to reach and everything is separated, but felt that the missions are very distanced from one another. Also had some bugs and vehicle issues where I lost a big part of the haul when a car broke in the middle of the hoard just because it glitched.
 
But to be honest, like the 1st one, while I enjoyed the environment and the intro I couldn't get into the open-world sandbox mode of it and was a bit disappointed that I had to juggle settlement building space. Also felt that even if well defended and placed build, the hordes just kept coming to attack it and I had to defend it.
 
I really enjoyed New Vegas but didn't manage to finish it and abandoned it at some point.
Skyrim is great and one of the ages.
Witcher series as well.
Dragon Age Series as well.
People also praise Dragon's Dogma
I loved Shadow of War, although it's not truly an open-world RPG.
 
What about ELEX from the makers of Gothic? Is there any substance there
 
Red Dead Redemption 2 I played it and finished, not 100% but I really enjoyed the level of detail and the world and characters. Especially the ending carrying on.
 

Ye Witcher 3, Red Dead Redemption 2 and most likely Skyrim will/should be on every top RPG list of the decade. This and maybe Legend of Zelda  Breath of the Wild.

breath of the wild was crazy fun to explore

Skyrim and that whole series has such a bad Ai it totally ruins the experience.

So many good ones!  I'd second Skyrim, Witcher 3, and Final Fantasy 14 (if that counts since its an MMO)

Witcher ( any of them ) , Elder Scrolls ( almost any version ), Gothic is up on the list too .

Of all time? Not Skyrim, it really doesn't hold up well today. I'd say The Witcher 3 is better of the two.
Last 5 years? Kingdom Come Deliverance. Very under rated. Had a bad launch and has sense then been patched up.

cneuhauser
May want to consider...
 
Morrowind
 
Oblivion
 
**These defined what it meant to be open-world

Oblivion was a great open world game. Morrowind I tried, but I just couldn't. After finishing Solstheim in Skyrim I fell in love with Tel Mythrin, Mushroom House best house. So hype for Skywind/Morrowblivion.

Yes ;)

Morrowind definitely changed everything for me as well. Especially first playing it after things like halo and final fantasy mostly. Still up there on my list of highest number of hours.

Witcher 3 and Skyrim !!

Lineage 2. Hands down.

In my opinion, the game that best uses open world mechanics and is conveyed to the player is Zelda BOTW. Red Dead Redemption simply created a wonderful and immersive world.

For me i would say:
 
Best of all Time is Dark Souls, if that does not count, i would say witcher 3.
in the last 5 years skyrim was pretty nice and death stranding was cool in it´s own way.
 
On other Systems it´s of course Zelda BotW