As an old time mmo player, the game's price is pretty standard, buy to play mmos are relatively new (since 2012 ~+-). In general though, you always have to look into where the money is. Is the population large? Is the customer support good? Are the updates frequent and of good quality (relatively bug free too). Is the game balanced or fair? Aesthetically pleasing?

I'll throw Guild Wars 2 in for a good example:

It's a fun game, different, and cheaper but your also looking at needing to buy your bank space (imagine if you only had on retainer with like two tabs), inventory space, character slots, glamour crystals and even your hair colour. FFXIV? Unlimited glamour, most armors in the game, and if I suddenly feel like dying my hair green, blue, or both I can do so anytime.

Then of course you're also looking at content: They're too damn different. That being said story in FFXIV is leagues better than GW2.

Then we can look at another one, Black Desert Online: Same appearance nonsense. Autoloot is tied to paid pets, otherwise it's stupidly inconvenient. Inventory space/weight is temporary by monthly booster packs. Market tax is affected by said booster packs. More exp gain from said packs. Armor itself is limited and bland in game with all the cool outfits for $30. Don't even get me started on the upgrade system.

Basically any older F2P game: Everything is locked behind paywalls or there's P2W loot chests/upgrade items.

. In general you'll see that in FFXIV:

It's consistent (some good, some bad here but you know what to expect). It's fair, and of good quality. It's not restrictive, and you're not locked out of any content outside of skill and expansion costs. There's more quality in the game toward emotes and socialization (as opposed to say BDO which is the most anti-social mmo I've played in years). Balance is fair (sorry machinists), or at least until the next few (fairly frequent) updates or so.

That being said, I play these other mmos too because they offer different things. Like being a sandbox, pvp oriented, action combat, or even just a bigger explorable world. Price is subjective when you consider what your looking to get out of it.