[mod]

You misinterpreted, yes. Custom setlists and downloaded songs are a big part of the intended use case of Guitar Hero.

[LocalH]

Custom setlists were most definitely not a big part of the intended use case, as they were hacked in after release by modders.

Downloaded songs were part of the intended use case on the lead platform, but no official DLC ever came out for the PC version to make use of it.

Having a setlist with 200+ songs was probably never even tested.