I usually play games on “normal” difficulty these days, for a balanced challenge. However, I don’t particularly enjoy boss fights, or at least I don’t enjoy the extra challenge associated with them. Was thinking it would be nice if games had a separate setting so I could just set boss fights to “easy”, while not making the rest of the game less challenging as well.
That is a question where the answer is very complex. You’d have to break down different game design philosophies, think them through, and then apply them to specific games.
In general, I have two gut reactions:
If players are desiring to change the difficulty of the bosses compared to the rest of the game, the devs have to ask if there is a failure of design on their part. An example of this would be Dues Ex Human Revolution, which was an immersive sim that supported many different character builds, except the boss fights which were entirely based on combat. This created a frustrating and unfair situation to players not making a combat built character. The solution was that the boss fights were completely redesigned in the Director’s Cut release to support alternate builds. This is one example, but naturally there are many more. If a game has a “that boss”, the devs should look at it and examine if there is a problem with the design. Is a battle too comparatively difficult? Too tedious? Only suitable for certain builds (in games with builds)? Is the battle too much of a departure from standard gameplay in the rest of the game?
A popular game is going to get mods. If there is a strong desire in the player base, the mod is going to happen regardless of dev stubbornness, so devs may as well just give the people what they want. If a game is praised but has outcry for boss difficulty sliders, either put it in officially or incorporate it into the sequel.