What the Heck is a Faulty Generalization?

Often when confronted with the fact that a belief is absent from Scripture, individuals will appeal to the Trinity. The claim assumes that since the term "Trinity" isn't used, yet this doctrine is regarded as not only sound but foundational... then any doctrine can be regarded as sound despite being absent from Scripture. Idol Killer's third entry into the YouTube Shorts format highlights how this line of argumentation Argues from Silence by way of a Fault Generalization (logical fallacies).