I still see some guy who are just terrible online.
These days, the difference between live and online play is the delta of competition you'll encounter.
Live, sure, occassionally you'll play a guy who is like 80/5 FR. Even the weaker live players have a field day pointing out how bad he is. But in general, though, your loose passives won't be that loose/passive, your maniacs won't be that maniacal, and your nits will be...well, no, the nits will still be the Rock of Gibraltar. What you'll also get less of live are absolute crushers. I have a few friends in the live game that are dominant, but most pros I know are simply grinders, trying to play a solid 15/11 FR style (limit hold em), take a half a bet an hour out of the game, and go home. They'll play straightforward and won't go for soul-crush plays with any deep understanding of your range/tendencies.
OaTOH, online 6 max FLHE is full of some absolute morons (52/7, 80/52, 90/47, 39/0 are all guys I play against regularly) regarding the game of poker. Some chase any discernable draw until they're confident they are drawing dead, some constantly try to barrel you off a hand, some attempt to free card in position religiously. They all lose at a velocity I couldn't fathom (like -15 BB/100 type guys). But on the other end of the spectrum, you get LAGTAG crushboxes who just play their hands really well. They play a solid 30/23 - 39/30 6 max style, they go for thin value, they bluff, they take lines that can be indicative of a wide range of hands (meaning you can't make the exploitative laydown of QJ on J88-2 when the fish who just cold called your raise and called the flop suddenly springs to life on the turn). Regularly when I play higher limits (15/30 or 30/60), my table will consist of myself, 3-4 strong regs, and 1-2 total fish. Easily tougher than any live game I'll play.
So long story short, you'll come across more experts online, but you'll also come across more total idiots who want to slam $10k down and start flinging $.