It doesn't help that the majority of people who bemoan the loss of games like UO quickly reveal themselves to be the sort of psychotic players who are the exact reason games like that no longer exist. You'll hear things like "I miss being able to slaughter dozens of people and take all their stuff". Ok great, but your average player hates that sort of game. And you need a high prey/predator ratio to satiate such desires.
I say this as someone who thinks of early UO as the best game they've ever played. I didn't mind that type of player, even spent most of my time fighting with/against them. But I also recognize that this segment is why we can't have nice things.
I am one of those rare people who actually really enjoyed the thrill of playing a miner (or some other crafter) and having murderers show up and try to kill me for my valorite ingots. It felt like high stakes (in game terms, low stakes in real life terms) hide-and-seek!
Over the years I ended up wearing many different hats, of course. I had red characters and thieves and mage-thief hybrids (by far the most annoying character for people to play against). I participated in guild vs guild combat, I had a tamer, a bard, a smith, a fisherman. I loved everything there was to do in UO. On a free shard I even dabbled in programming, writing a bot to automate shearing sheep and storing the wool in the bank. That shard had a really high spawning rate for sheep so I was able to earn enough gold to purchase a keep to share with my friends in about a week of real time!
Likewise, it's just that we were a severe minority.
I spent most of my time either PvPing in some form and/or heavy RP activity including tradesperson type stuff. My main character was notoriously red-but-actually-good as he would fight against wrongdoing even if it earned criminal flagging. So I wound up with a pretty diverse set of friends no my server.
On my shard there was a cluster of PKs who were actually pretty mature/sane, many of them got into the RP side as well with one group featured in Wired. We became OOC friends and often would concoct RP reasons why my guild and those groups would band forces against the K1ll3rd00d type PKs that would roll around. And that's how I got most of my PvP enjoyment.
The skill gap issue is huge in games. When a game is popular you have plenty of people worse than you at the game to stomp. When it becomes niche its just you against the pros who play nothing but this one game for thousands of hours, and it becomes a lot more frustrating to get into a game.
I thought the reason we can't have nice things is because everyone wants a game where they can obtain things and keep them forever except for in extremely rare "fair" circumstances.
I say this as someone who thinks of early UO as the best game they've ever played. I didn't mind that type of player, even spent most of my time fighting with/against them. But I also recognize that this segment is why we can't have nice things.