Yes, Rhystic Study is a format staple, but Commander is more of a casual format than it is a competitive one, and this card is also not as good as many give it credit for

Top Rakdos Commanders Valgavoth, Harrower of Souls 29,424decks Kuja, Genome Sorcerer 20,073decks Deadpool, Trading Card 16,398decks Prosper, Tome-Bound 13,863decks Judith, Carnage Connoisseur 11,902decks Gev, Scaled Scorch 11,657decks Shadow the Hedgehog 11,025decks Ob Nixilis, Captive Kingpin 10,507decks The Infamous Cruelclaw 10,133decks Rakdos, Lord of Riots 10,038decks Rowan, Scion of War 9,028decks Strefan, Maurer Progenitor 7,966decks Kardur, Doomscourge 7,345decks Ozai, the Phoenix King 7,168decks The Lord of Pain 7,117decks Laughing Jasper Flint 7,009decks Evereth, Viceroy of Plunder 6,902decks Juri, Master of the Revue 6,734decks Magar of the Magic Strings 6,525decks Blim, Comedic Genius 5,765decks Anje Falkenrath 5,621decks Rivaz of the Claw 5,466decks Raphael, Fiendish Savior 5,448decks Rakdos, the Muscle 5,301decks Xantcha, Sleeper Agent 5,288decks Asmoranomardicadaistinaculdacar 5,229decks Grenzo, Dungeon Warden 5,189decks Imskir Iron-Eater 4,977decks Mogis, God of Slaughter 4,751decks Alesha, Who Laughs at Fate 4,721decks The Master, Multiplied 4,669decks Grub, Storied Matriarch 4,647decks Black Waltz No

The swirls of wind racing around him scream of transformation as if Urshifu is reigning in all of the energy around him to power up a deadly attack that c an't be escaped
Mythic rares tend to show up at lower-than-expected rates in most Collector Boosters, so they often hold their value pretty well regardless of how much Constructed play they see