In fact, Memory Capsule, a tool card, fills the gap in the current format
(2023-02-04) Once the equipped creature attacks and the triggered ability resolves, you get an additional combat phase even if the equipped creature doesn't survive the first combat phase
We're not ramping for anything in particular (we don't desperately need our Commander to win or play the game), so we're just making a bunch of mana for the late game, when there's a good chance we'll want to do a few huge things
So, they got weaker, not because of a rules change like getting rid of mana burn but simply because of a cosmetic change to the game
Count on Luck is the red Phyrexian Arena
Players will find familiar faces and concepts like Auron, Venerated Guardian, Summon: Valefor, Blitzball Stadium, and even Sin, Unending Cataclysm