You may not be able to literally select which cards are going to the graveyard with each discard spell, but by paying attention to what cards your opponent keeps and what they give up, you can try and time your punches to cut off their decisions and paralyze even the most powerful Constructed decks
Bellos trigger only affects non-Equipment Artifacts and non-Aura Enchantments that cost 4 Mana or more, which means its better to have a few of those down before Bello actually becomes useful
There are a lot more cards for you to potentially face in the Modern pool compared to Standard
When Reach for the Sky is put into a graveyard from the battlefield, draw a card
Since Dominaria , however, things have become much more clear about Jaya thanks to the first ever planeswalker printing of Jaya Ballard and, more recently in War of the Spark , Jaya, Venerated Firemage where shes the kick-ass grandma we all wish we had
Conclusion Hopefully this article has made the idea of sentiment and how it relates to picking good spec targets clear