As someone that has at least tried all 15 entries in the series, including some of the spinoffs, I don't understand how the author can claim that Final Fantasy XI is tough to get in to unless you have people to play with. In recent years the game has become as accessible as XIV by using a system called Trust, which let's the player choose non player characters to create adventuring parties with. It's no longer necessary to look for people to run main story missions with since you can build your own party, instead. That's not too say you can't, however, just that there's a lot more flexibility in deciding how to tackle content.
I'll admit, sometimes the system can be a bit janky, but it's because the game is 20 years old, as previously mentioned.