Bygone Thought

Strategy
is the go-to 1-drop in self-discard decks as it provides a nice threat for its cost with an entomb trigger that you can use to your advantage. The card is arguably more of an archetype enabler rather than a disruption card.

The entomb discard effect is symmetrical, it can make it undesirable for the opponent to trigger the entomb, which might leave them unwilling to respond to it. This is another angle on the card, while the entomb is certainly good at giving it a longer lifespan, it also is technically weaker than it would be as an summon since it's harder to trigger its effect on early turns - where discard would be stronger as many decks tend to accumulate cards in their hand as the game progresses.

The card is reasonably powerful and it wouldn't be entirely unreasonable to main this card even off-affinity given its potential can be utilized fully.

Trivia
The earlier designs of the card, that didn't get voted in, made players discard cards randomly, which would have been stronger as far as disrupting the opponent's game plan goes, but also harder to utilize for yourself as a self-discard enabler.