I've been playing Assassin's Creed Odyssey. It seems to be mostly good, but does have a lot of bad things in it too. One of them is level scaling. Computer games tend to have that, and I fear even "table top" RPGs with level mechanics may suffer from this design flaw. In fact, the game doesn't have to have level mechanics for the designers (or Game Masters) to fall into perpetrating this mistake.
In case you don't know what level scaling means, I'll put it simply: as the player character(s) advance in levels, the opposition also gains levels.
Levels in general is a stupid, but often used mechanic to indicate how powerful someone is. Usually, following Dungeons & Dragons, levels are really only or at least mostly about fighting ability (in some cases with magic perhaps, but still it's mostly about the ability to cause and to take "damage").
The main problem with level scaling is obvious:
It seems that no matter how good you get, everyone around you also becomes that much better. In effect, your hard earned "experience points" really didn't change anything, you're still just as good, compared to others, as the designer intended.
In some games, this means that the simple town guards that you meet in the beginning will be level 1 fighters, but later on you will meet simple town guards who are level 20 fighters.
In other games (AC Odyssey included) this means that soldiers or your enemies in one area will be mostly level 5 fighters while in another they will all be level 40, because the story of the game is obviously intended to take you to those latter places only later in the game. In some cases, those level 5 soldiers are supposed to be at war with the level 40 soldiers, yet somehow the latter don't just quickly crush the former. Weird, huh? Or plain stupid design, rather.
How should the games (or RPG campaigns) be designed then?
Realistically. That's the simple answer.
First of all, levels would ideally not be used at all. If they are used, the significance of the difference between consecutive levels (e.g. level 1 and level 2) should be small, especially if the game allows progress through dozens of levels.
In fact, there should be a reason why the player character is able to progress faster than normal, if that is the case, be it divine bloodline or whatever.
Second, and most important, is to be consistent about levels. Town guards everywhere should be pretty similar in quality, unless there is a good reason within the story for some of them to be better or worse than the average.
The world should not change around the player character, but rather stay relatively static, or change according to whatever realistic reasons it does change. In a mundane world, the abilities of soldiers in two opposing armies are likely to be very similar, and also similar to many other soldiers. If on the other hand, a mighty god of war should appear, he might be able to change his followers into much more effective (and horrible) fighting machines. But even those demonic soldiers cannot continuously get better and better conveniently at the same pace as the hero of the story.
IMHO, the above is pretty damn basic for RPG designers/Game Masters. That big game companies still fail at this, after decades, I cannot comprehend. If any company would like to hire me to tell them how to improve their games, I'd be happy to take the job. 😀