Tanarii, you keep equating module with non tailored, especially AL. That's not true. In fact, there's specific guidance in the AL DM guide on how to tailor an AL session to the players. Yes, there are limits to keep it legal, but you're allowed to adjust encounters, or in fact make any changes that "stay within the original spirit" of the module. The big restrictions are on things that transfer between chapters--XP, treasure, and renown. Even maps can be adjusted if desired.

I see no indication that "no tailoring" is the default for modules or organized play, and I do see much evidence to the contrary. Modules are designed to serve as aids to the DM, not holy writ. The whole first chapter of the PHB says that it's your world, even if you're playing in Faerun and following a module.

This whole thread is based on a mistake--the only job of a DM is to facilitate fun. For some groups, that means not tailoring anything. For others, it means a custom experience. Good DMs give the group the experience they want. Bad DMs don't, for one reason or another. Tailoring or not tailoring is orthogonal to being a good DM.