I can't speak for anyone else's experience, just my own, but when I came over at the end of Stormblood from WoW it felt like night and day between communities. I'm sure there's bad actors out there, this being the internet and all that jazz, but every single time I join DF I expect to complete it without issue, and with people being positive.
In WoW, I expect groups to break down, I expect if we wipe in LFR to see people leave and others start calling others slurs, if I join a partial premade in dungeon or island expeditions I expect to get kicked right before the final boss/last bit of it and earn a deserter debuff on top of gaining nothing for the run, and for Blizz to do zilch about the people who join in premades with the intent of kicking the pug at the last moment. If people find out I'm a girl I expect long term harassment, being stalked to discord. In classic people abuse the automated ban system so hard at one point so many guilds going for scarab lord got banned because competitors were using the system to remove their competition. If you say anything negative in classic you get told to go to retail, when I bring up retail beta issues I get told off and people accuse me of being negative- then after launch those same people get furious that we beta testers didn't do our (unpaid) job and find the bugs we told them about months ago.
WoW's community is such a miserable experience it took me until deep into Heavensward to accept that the positive chain of DF runs was the norm and not just some fluke. I felt nervous watching the Ifrit cinematic because in WoW I'd have been kicked for doing that, I felt wary dying to mechanics like the Angry Mwahai? in WoD cuz in WoW, I'd have been kicked for daring to not know a fight before I do it the first time. Now, I don't feel any worries about doing casual DF content in this game, because it feels like learning things by doing them, messing up, sometimes not being optimal in a game that's meant to be fun isn't some sort of crime deserving of harassment.
I think having a positive, non toxic community is not the same as having an extremely toxic one that encourages bad behaviour, and if there are some in FFXIV who abuse the report function and that actually works, of course that's bad. Some seem under the impression though that WoW players, because they're outwardly toxic, don't do 'subtle' toxic things... which is incredibly wrong. The scarab lord is one incident, but all through classic it was a constant problem with players abusing squelch to silence others trying to sell rare items (enchants, LH helm, devilsaur leather, cloudkeeper), with top raid guilds targetting other top raid guilds with mass reporting, with guilds putting spies into other discords to cause trouble/headhunt/harass players.
I wouldn't be afraid of being assaulted or spit on if I went to a FFXIV fanfest live event- I'd expect it if I went to Blizzcon with an Alliance shirt.