I haven't even been playing a year, so i can't comment on the olden days. Yes soloing is difficult for most jobs, probably like it was before. The new expansion has options for gaining experience as a soloer, but it's still not fast. This game is definitely based on playing with groups, which isn't always my thing either. I've worked one job to the max. The rest I work here and there, but most often lately I'm crafting or piddling around the new expansion solo.
I've never played WoW, but I've met plenty of people in FFXI who left the game for WoW and came back not long after. It may be a longer road leveling up here in FFXI but it's a more rewarding experience than in WoW, from what I've heard.
Welcome (or welcome back) to Stratics, by the way
