It's almost military precision.
On behalf of dead WWI soldiers I find this offensive.
Brutal murder is low tech.
It’s like the original massive scale organization.
(Thankfully in the US we worship the 2A and its most twisted interpretation. So our toddlers do shooter drills. /s)
Or, gather a group of people, tell them to find a rock, and go bash the other sides head.
The ak-47 famously only needs the first item in that list.
That being the key to its popularity.
https://www.youtube.com/watch?v=DX73uXs3xGU
https://www.youtube.com/watch?v=YAneTFiz5WU
As far as cleaning, AK, like many guns of that era, carries its own cleaning & maintenance toolkit inside the gun. Although it is a bit unusual in that regard in that this kit is, in fact, sufficient to remove any part of the gun that is not permanently attached. Which is to say, AK can be serviced in the field, without an armory, to a greater extent than most other options.
But the main reason why it's so popular isn't so much because of any of that, but rather because it's very cheap to produce at scale, and China especially has been producing millions of AKs specifically to dump them in Africa, Middle East etc. But where large quantities of other firearms are available for whatever reason, you see them used just as much - e.g. Taliban has been rocking a lot of M4 and M16 since US left a lot of stocks behind.
And Western supplies are mostly 5.56 for obvious reasons, although there are some exceptions - mostly countries that have switched fairly late and still have substantial stocks of 5.45, such as Bulgaria. But those are also limited in quantity.
So in practice it's not quite so simple, and Ukraine seems to be aiming for 5.56 as their primary cartridge long-term, specifically so that it's easier for Western countries to supply them with guns and ammo.
Soldiering isn’t sexy, it’s digging trenches, cleaning kit, and eating concussive blasts waiting to fight or die.
You don’t sit in a bunker all day waiting to defend a trench and not clean your gun.
They are much less likely to.
We have instinctive repulsion to violence, especially extending it (e.g. if the rock does not kill at the first blow).
It is much easier to kill with a gun (and even then people need training to be willing to do it), and easier still to fire a missile at people you cannot even see.
If you caused enough damage such that someone could not later be recognized, I wonder why you are not in prison.
Funny you mention crossbows; the Church at one point in time tried to ban them because they democratized violence to a truly trivial degree. They were the nuclear bombs and assault rifles of medieval times.
Also, I will take this moment to also mention that the "problem" with weapons always seem to be how quickly they can kill rather than the killing itself. Kind of takes away from the discussion once that is realized.
It's that we have technologically engineered things that are destructive enough to get even past that threshold. Modern warfare in particular is insanely energetic in the most literal, physical way - when you measure the energy output of weapons in joules. Partly because we're just that good at making things explode, and partly because improvements in metallurgy and electronics made it possible over time to locate targets with extreme precision in real time and then concentrate a lot of firepower directly on them. This, in particular, is why the most intense battlefields in Ukraine often look worse than WW1 and WW2 battles of similar intensity (e.g. Mariupol had more buildings destroyed than Stalingrad).
But even our small arms deliver much more energy to the target than their historical equivalents. Bows and arrows pack ~150 J at close range, rapidly diminishing with distance. Crossbows can increase this to ~400 J. For comparison, an AK-47 firing standard issue military ammo is ~2000 J.