In the modern era, its purpose is different because it is a reliable extender due to its second effect, which allows it to special summon a Dragon-type monster from the hand or GY
Not only that, but it is a Quick-Play Spell, so you can surprise your opponent with an unexpected Monster to interrupt their plays
There is 1 in every 454 packs
In Limited formats, ideally, you'd want to have three or more lands for each card of the color you're splashing
When in doubt about what ramp to run, always go for the lower converted mana cost
Discard effects are predominantly black cards and most often sorceries (or abilities that can only be activated at sorcery speed) so that you cant make your opponents discard cards in their draw step