Whether CSMs can be cheats is an interesting and difficult question which needs to be discussed.
So they can be used to gain an advantage, this is clear. Is this enough for a cheat? I am not sure.
The question is if this advantage is
unfair. After all, CSMs are (like it or not) an official feature and every other player can install those CSMs as well.
Another question is whether CSMs constitute 3rd party tools. Well, this is another difficult question. Yes, they are written from 3rd parties. However, one could argue they act more like plugins. But technically, they are still pretty darn similar to 3rd party hacking tools.
Note I condemn CSMs as they are implemented right now a lot. However, I find it hard to automatically call them “cheats”,
because they are an official feature.
But it's still not so simple: CSMs are an intended and official feature
in Minetest. They are not a feature of games and servers. From the viewpoint of Minetest, CSMs are never cheats, as they are an intended feature, and as long the CSM uses the official API in the official Minetest, there is simply hacking attempt involved.
By that logic, one could argue that CSMs are never cheats.
However, from the viewpoint of games and servers, this is getting more problematic: CSMs completely throw all assumptions you could previously make about the player under the bus.
From the viewpoint of a game, a CSM could
very well constitute an unallowed 3rd party tool and thus a cheat. CSM mean loss of control for game makers and server operators. Let me recite my definition of “cheat”:
In the context of video games, cheating is when you break the rules of the game to give yourself an unfair advantage.
Let us look at a simple example, oredetect. In a game in which you dig and search for ores, the embedded rule of the game is that you do not just know where to find every ore without looking at it. Oredetect throws this embedded rule under the bus, thus breaking it, thus gaining an unfair advantage over players
who might not even know that CSMs exist.
Under this logic, CSMs CAN be cheats. Many server operators were heavily opposed to CSMs (at least in its current form) for precisely this reason.
HOWEVER, one might argue AGAIN that all games are
based on Minetest, extending it, so to say, so they “inherit” all the embedded rules of Minetest, which would in turn mean that CSMs aren't cheats, ever. Since everyone can install CSMs, it's not unfair.
This argument might in turn be dismissed again by the anti-CSM side by simply saying that the game in question did not anticipate or welcome the addition of CSMs into Minetest.
You see, this matter is complicated to the point it might you go nuts. :D
One solution out of this dilemma would be simply writing down on server side whether CSMs are forbidden or allowed. This sucks.
Now can CSMs be cheats? Well, I don't know, really, but I tend towards “yes”. I also like to hear your view on CSMs.
What IS clear is that CSMs can be very unfair, like oredetect.
This is a problem: The level playing field is destroyed by CSMs. To restore the level playing field, all players would be basically forced to install all CSMs everyone else is using in order to stand a chance. This just complicates Minetest usability, ironically.
Since CSMs are tolerated in Minetest, it is impossible for a server to enforce some rules of the game, like “you can't look through stone”.
So CSMs might or might not be cheats, but they sure can be unfair like hell.
I myself do not use any CSMs, by the way.