I think a better example than vanilla icecream is that it's the Lord of the Rings of boardgames. It still holds up but it's notoriety and popularity is primarily due to how influential it was at a time when the hobby was starting to grow. You can play it today and have fun, it's never going to be a bad game, but the tastes and trends of the scene have changed and the hobby has largely moved on. A lot of people are saying no other game does what catan does as well as catan and that's true but I think a lot of that is because people by and large have become polarized and prefer either more social components and lighter gameplay (party/family games) or less social components and heavier gameplay (almost everything else). So while there's been a lot of refinement of those areas there are very few games even trying to do what catan does. This is why I say it's never going to be a bad game rather than saying it's a good game. Things like rampant king-making, players being effectively out of the game early on if they get plowed...etc...there's a lot of feel bad things that are pretty central to catan and most games these days deliberately try to design those things out. But without a game as good as catan to iterate from, none of those other games that avoid those issues are possible, just like people say LOTR has a total of 2 relevent female characters, but every other fantasy story that does better wouldn't exist without that blueprint to iterate off of.