Killing digital dragons with friends is fun. Higher tier PvE in this game has a huge potential that's not fully realized but it still contains some very enjoyable nuggets of gameplay. Raiding is fun. Doing challenging dungeons cooperatively is fun. This game has aesthetically great instances to support it. What isn't fun however is running around from point A to point B clicking on hotspots to watch another movie about literal who characters.
At this point I believe that story in XIV is praised only as a reactionary thing after Final Fantasy being mired for years by pretty terrible storytelling quality in single player titles (and in my opinion this still hasn't changed - I find XV to be a terribly handled game). But look at the actual gameplay that the storyline campaign involves. It's awful. Dozens upon dozens of single player only scenarios is wildly inappropriate for a massively multiplayer game. Making hours of cutscenes doesn't really make for a good video game story. Very little in XIV takes advantages of video games as a storytelling medium, let alone MMORPG as a storytelling medium.
If an MMORPG is trying to tell you a story about a massive battle between Power A and Power B... it should probably be some kind of massive battle players can participate in. Not a movie. I'm a huge fan of storytelling-through-mechanics and storytelling-through-environment. Or at the very least, storytelling through not wasting people's time.
Let me give examples. One of the best stories in games recently can be found in Nier Automata. Why is it so good? Well it still has cutscenes. But cutscenes are limited only to what they need to tell. A lot of other story elements are told through just the way environment is portrayed, or through the way bosses act, or the way NPCs act during gameplay. And when the game wants you to trek a bit, it will still find a way to tell you something just in the background (a good example of that is when you leave Amusement Park for the first time and are on your way to Pascal's Village, things will be happening en route instead of in a movie).
Now look at XIV. Its story is told almost completely in the format of "Go here, click on this thing, watch cutscene". Sometimes you kill an easy enemy. They took questing format from WoW but didn't understand that even WoW constantly tries to spice up the tedium with random unique mechanics. Like, sometimes a quest will turn into a shooting gallery, other times you'll get to ride a huge killing machine mowing down hundreds of enemies. The best XIV does is giving you mandatory party dungeons. Although you can spot a "Quest Action" HUD element in Stormblood letter from the producer so they've picked up on this I think.
Like... It doesn't matter how good the scenario is in a video game if you're not really involved in it as a player. And the scenario is not that good! It's padded, it focuses too much on boring Scions, it's not even particularly well-animated most of the time. Yeah, there's been more good than bad recently, but damn it can be such a slog. Stepping into the last quarter of the Palace of the Dead was much more breathtaking than listening to another soliloquy by Y'shtola could ever be. Seeing Bahamut use Teraflare the way he did in The End of an Era was much cooler than listening to Illberd elucidate about muh Ala Mhigo for the xth time.
tl;dr I cannot in good conscience say a story in a video game is good if it doesn't take advantage of the medium and doesn't exist to support the process of playing.
FFXIV is a great FF game for story. In fact, i'd rate it very highly as one of the better titles.
