Do i sense a sort of "fear of lithium" into you my friend?
Not at all. An understanding and a respect for lithium maybe. My fear is for others with lithium cells. Some times the warnings are overstated, some times they are understated. "You'll be fine", approach, "What could possibly go wrong?"
Most of my experience with them is in high discharge LiPos in 3 series. There are so many good documents online and also so many dumb mistakes that people have made with them. They can expand or even explode is overloaded as some can deliver flooded lead acid rates of discharge in 3 digit amps, 30C, 40C even 50C discharge are common.
If you want to talk battery abuse. My 450 RC Heli runs on a 2200mAh 3S pack. It draws about 200W sustained, 300W in bursts, 16-25 Amps for 7-8 minutes and the battery is dead. The battery will be slightly expanded, puffy and very warm to the touch on landing. It will be allowed to cool, balanced and charged at 2C 4.4amps to be flown again. All packs are balanced to storage voltage when I return home.
18650s are usually much lower output, they are also encased in a metal sealed container, so maybe you are right, they would be much safer, unless shorted.
The other thing that concerns me in the electronics hobby is that while 90% of people use them in 1SnP configurations, which is fine unless a cells fails and they are no fuses, the 10% of people needing 2S, 3S and 4S don't seem too bothered about proper balancing circuits. The number of youtube videos were people are trusting charging a multi-series pack to a single connection BMS and running several amps into it is quite high. Some believe they can occasionally check the cells manually and put them on a balancer once in a blue moon. This is NOT how it works. Series cells get out of balance fairly quickly, particularly at higher discharge and higher DODs.
The later is most likely due to the complete lack of available balancing BMS boards that actually work or have any guts/smarts about their balancing. 10R or 100R resistors and mosfets on a 10Ah+ pack is not going to cut it if it's in constant service. It just won't keep up and it will waste a whole load of energy trying. Some cells will end up undercharged before cut off, some overcharged during charging.
Most of better BMS multi-cell boards I have seen have tiny wee resistive balance circuits and offer barely usable and partially dodgy individual cell protection.