Yes…
You probably do, and there are two reasons.
Most obviously, you’ll be able to hear lower. If you’re making EDM, Hip Hop or anything adjacent, you’ll be routinely working with instruments and sounds that dip below ~40Hz.
Even if you’re working in rock n roll, acoustic, or podcasting for that matter, adding a sub to your mains and delegating the bottom ~octave of your material to a sub will unburden your mains. This contributes to healthy headroom, lower distortion. It’s… better!