As a general rule, yes

Consider a boat weighing 20kg, a paddler weighing 80kg.

You're now displacing 100litres of water, the way in which you displace that volume has a lot to do with how easily the boat will handle.

• If you choose to displace it as a wide cylinder on a vertical axis you will have high maneuverability and low forward speed.
• If you choose to displace as a narrow cylinder on a horizontal axis (aligned fore/aft) you will have high forward speed and low maneuverability.

Why?

Simply put: Drag

• The wide short boat is primarily suffering from form drag
• The long narrow boat is primarily affected by skin friction

Image from above linked wikipedia (drag) article

What this means in practice is that in a short wide boat, for example a playboat (Length: 168 cm Width: 64 cm Weight: 14 kg), you'll hit a low top speed where a wave has built up in front of and behind you (bow wave and wake) between which you're stuck, you can't break through the wave ahead, you can't break through someone else's wake to get ahead of them. Most of your energy is going into moving water around rather than moving yourself forward.

If you were in a long narrow boat, for example a wavehopper (Length: 400 cm Width: 60 cm Weight: 18 kg), you'd cruise past the playboat while doing a lot less work and barely noticing that you'd cut through the waves, its speed is limited almost entirely by how fast and efficiently you can move your paddle.

From this point on physics SE is probably your friend.

Everything is a compromise. For my purposes the polo boat is a perfect compromise, but then I play polo. In a straight line someone in a sea kayak or any given racing boat is going to be faster, straight lines are boring.

The real answer isn't in asking whether a longer boat is faster, it almost universally is, it's in asking what you want to do with your boat.