In weightlifting, Olympic lifters tend to peak in their early to mid-20s. The snatch and the clean & jerk are over in about a second, so they reward explosive power and a nervous system that fires fast. Powerlifters often peak in their 30s or later, because a heavy deadlift is a slow grind that rewards accumulated strength, tougher tendons, and years of learning how to use your own levers.
BJJ has the same split.
The young game is speed and elasticity: explosive guard retention, wild scrambles, exploding out of bad positions. It's exciting, and it works, but it burns fuel fast.
The long game is density: heavy top pressure, small adjustments in leverage, and positions that are slow, tight, and hard to escape. That kind of game takes years to build, and it keeps growing as you do.
Neither is better, and you don't have to pick just one. But if you're a little older, or a little less springy than you used to be, you're not falling behind. You're building the part of the game that compounds.