The DoubleTree at Sea World isn't a hotel that comes up very often in this forum. I checked out the Sea World/Discovery Cove forum, but didn't find much information beyond basic comments from years past like:
"I enjoyed our stay @ the doubletree. Very cost efficient, clean & complimentary breakfast was good."
That thread:
https://www.disboards.com/threads/hotel-choices-around-sea-world.3603413/
Note: This hotel only offers complimentary breakfast to elite-level Hilton Honors members. That's the frequent guest program for Hilton Hotels and Resorts.
While I haven't stayed there, I do know the DoubleTree at Sea World has two distinct types of rooms. The cheapest rooms are located in 2 or 3 story buildings with exterior entry. I've always thought that exterior entry rooms are noisier because the bathroom is on the inside of the room. So, the living space (bed, seating area) is closer to the corridor where people are walking (and talking).
With an interior entry room, the placement of the bathroom near the door provides a little extra space to block sound.
A quick glance at photos on the official website and Trip Advisor shows that at least some of the exterior entry rooms have "hard wood" flooring. All of the interior entry rooms in the tower look to have carpeting. Hopefully, the hotel didn't skimp on the underlayment on those "hard wood" floors. But, I have a neighbor with them and I hear every step when she's wearing heels. So, I'd be wary of that type of room if you're seeking quiet.
My recommendation: Book a tower room, if possible.
Hopefully, someone who has stayed at the hotel will provide some feedback.