Here in Germany it depends on the region. But even within one region it can be different from friend group to friend group.
I grew up in southern Germany with handshake as default greeting. Except women often get a hug instead. If you know someone well it's more likely to greet with a hug with men grasping each other's hand before a short hug and slap on the back. However, if you see them a lot you might just give them a nod. On the others hand id you haven't seen them in a while they get a hug.
In East Germany, where I live now, it seems to be much more common to hug your friends. Interestingly some will put their head on the right, reaching with their left hand over your shoulder. Which can be very awkward, when you are used to the opposite and almost kiss.
Here in China it's basically nothing. They don't even have to greet you. They only do the formal stuff with people they need to be chummy with. Sad but true.
I'm an expat here, and it applies not just towards me but to any Chinese-Chinese new acquaintances.
Japan was totally opposite and awesome, bowing to an old lady and getting into conversation with her was one of the most memorable experiences for me.
Mexico. Definitely a hugger and kisser country. Except man to man, that's suddenly a handshake situation, unless you are close you get a hug, or if you are too close (father and son, for example) you may get a kiss.
No touchy-feely here. Touching people from different gender is improper, while touching people from the same gender is gay (unless you're a girl). Can you guess which country is it?
Imagine my surprise when I visit a country where hugging and kissing (on the cheeks) are the norm when I was in highschool. I was like a deer in headlights. "My relative never even hugged me, yet these complete strangers greeted me with hugs?" and "this girl kissed me on my cheek when saying goodbye? Wtf I never even did any handholding with a girl before?!"
UK: Neither, there's handshakes for professional introductions and such but if I'm greeting someone normally, a friend, family member, etc, I'm not trying to touch them at all.
Dunno what it's like in other western/European/Central European/Slavic countries but here in Poland, if you're a boy, you're deprived of hugging by around 6th year of life, started noticing youth nowadays it's more huggy than in my times (beginning of the century), I remember getting a man hug from a fellow student (friend?) because of my 18th birthday, and thinking to myself 'wow this hugging thing is kinda nice'
I think cheek kiss in the uk is very much a thing for the older generations. I've only ever seen millennials and below do it to the elderly and usually it's someone they know, not someone new.
Well, since Covid happened some people have become more aware. And currently everyone is annoyed at work because half the people are sick at home and you have to compensate. The other half goes to work but they're also sick and sniff and cough and spread the viruses. I'm vastly exaggerating. But it certainly feels this way. I've stopped hugging my friends so we can make it to christmas and don't mix the viruses ;-)
I think the majority of people don't care that much.
The US is too big and diverse to generalize, but I was raised with a "hugs for family and friends, fistbumps for social equals, handshakes for formal situations" heuristic.
USA, Minnesota. People hug but ask if you're a hugger first.
I think it's funny that only 2 options were given. In India the norm is clasping your own hands together and saying namaste, nomoshkar or some other greeting. No touching. In east Asia a very slight bow is incredibly common.