I have a good buddy with a similar story. He quit smoking by vaping and reduced his nicotine down to the lowest level. Although he seemed to suggest there was still a decent jump between the lowest level and zero. He has yet to be able to get to zero and quit vaping despite him having that as a goal at one point.
While we don't have decades of data, I have to think vaping is less dangerous than smoking, but any chemicals/vapor you are continuously forcing into your lungs are likely to have long term negative effects in my opinion.
Just the elimination of the smell of smoke with vaping has been massive. I remember going to bars in the early 2000's or pool halls in high school. Your clothes and hair would reek after.
There can still be potential of harm from inhaling vapor and nicotine, sure.
But, that's my decision to make, IMO.
I have never actually had a goal of actually quitting, personally.
I vape 3mg nicotine, which is the first jump up from 0. I would not call it a sizeable jump at all. Most people are vaping what is essentially 12-15mg nicotine (it gets complicated if we start talking salts) and all the Juuls are super high nicotine.
Those high levels are important when trying to quit actual cigarettes, but, I hate them. its way too high.
The fact that no one cares if I knock back a handle of vodka daily but they do care how much nicotine I intake is rather infuriating.
My personal addiction is more of smoking than the nicotine itself but I enjoy the combo. Even if I use a patch, I'll still want to smoke the whole time.