I've noticed bigger modpacks are actually overwhelming, and as such have less to do.
Indeed. Its a common concept in the sales community called "analysis paralysis." When you give a client tons of information and options, they'll often choose to do nothing. As a sales noob I'd often flood clients with options and information. They'd always have to "think about it." Once I went into a closing appointment and only offered 2-3 options, my close ratio skyrocketed. Lomited options forced a need to make a decision. Less was actually more.
The same goes with mods. We often see people complain they have nothing to do in game. These same people will be using huge packs like Yogscast complete with 200 or more mods and no system hangups. That makes no sense. Even if all you did was grind through every mod in that pack you'd still have months of gameplay and mod learning. The options overwhelm them and they stop playing
The best evidence of mod glut/analysis paralysis is the popularity of HQM packs. These packs eliminate excessive options and offer directed gameplay. The amount of mods is far less yet people love them. The recipes in the packs are often changed to limit & force progression, terrain is usually sparse, and dear lord the grinding is insane. But people love them for offering less options, directed gameplay, and "achievement".
This clearly shows how correct Santa is in this statement. Its actually a fairly common occurrence. If you really want to see how options stifle people, try listening to any couple, with $20 or more to spend on Friday night, when the subject of "what are we going to eat" comes up.