This is correct, the buzz is lack of oxygen.
Most of the noticeable effects of nicotine are in the withdrawal symptoms. That's why I think most vapers end up on a slow chain vape cycle which just keeps nicotine levels topped up to avoid that.
Very true! A smoker I know was watching me and the way I vaped. He noticed that I would take a vape, set it down for a few, pick it back up, set it down etc..... His remark: you don't let the nic level go down but you don't hit it constantly like one does with a cig.
With smoking, I didn't want to waste a single bit of that cig by letting it burn away. I do notice that when I wake up in the morning, I'm content to lay around in bed for a while.....a long while

before getting out of bed. When I smoked, as soon as my eyes were open I would have to get out of bed and start my coffee then have that first cig of the day. I now know how my hubby feels about sleeping in. I've never been able to before finding vaping.