It used to just be Commander sets, but now we have Universes Beyond, Secret Lairs, direct to Modern sets, and now a player who started in the last year and only purchased newly released products likely cant play most of their collection in Standard
A well-drafted deck with an appropriate sideboard can alleviate this problem, but in most scenarios, you don't want to include cards like Disenchant in your main deck unless you are certain that you are playing in an artifact and enchantment heavy meta
Weaknesses This deck has very few tools for answering your opponents players, instead relying on a large board that forces your opponent to answer your plays
Of particular note is low-mana enchantment Dreadful Apathy, which dooms the creature to which its attached to a wretched tedium
In true D&D fashion, it allows you to create your own character, which then becomes your commander
Vivien's Grizzly is certainly costed as a common, but you can still make use of it in bear decks, or maybe with Agatha of the Vile Cauldron