No worries, just name instant or sorcery instead.
Other prominent mechanics that incorporate (or freely enable) sacrifice include: Food, Clues, Treasures, Sagas, Unearth, Encore, Evoke, any other temporary tokens such as Faerie Artisans or Hostility, cards with Upkeep, Quests, Exploit, Casualty and now Bargain
Gilded foils will shine brighter in Commander as well because 100-card casual Commander decks in Magic: The Gathering can be a better place to show off expensive cards than competitive tournaments
Perhaps the craziest thing about that statement is that Tiamat is not unanimously the best Dragon Commander since the archetype also has access to cards like The Ur-Dragon
Clown Car is a mana sink for robot decks