Lulu wonders why her procedural code doesn't work in Swift's declarative environment!

func resetGame() {
        userScore = 0
        for _ in usedWords {
            withAnimation {
            usedWords.remove(at: 0)
            }
        }
    }

Ok, I admit. I made some assumptions that you have a background in procedural programming languages. It seems this way to me because I interpret your code in this way:

Set the userScore to zero
Then for each word in the array, remove the first word.
When removing the word, apply some animation!
Keep going until all the words are removed.

In SwiftUI's declarative world, you should tell Swift to draw a list using words in the usedWords array. But Swift should draw the list of words using animation whenever the newGame value changes!

This ensures the view is redrawn with animation whenever the newGame boolean is reset.

//  RemoveWordAnimation
//  Created by Obelix on 5/3/22.

import SwiftUI

struct ShowWords: View {
    @State private var newGame = false  // For testing only. Force a newGame
    // This array changes, based on your Toggle selection
    private var usedWords: [String] {
        return newGame ? [String]() : ["Lorem", "ipsum", "dolor", "sit",  "amet", "consectetur"]
    }
    var body: some View {
        VStack {
            Toggle("New Game", isOn: $newGame).padding(.horizontal)
            List {
                ForEach(usedWords, id: \.self) { someWord in
                    Text("\(someWord)")
                }
                // DECLARE this animation happens whenever the newGame variable changes.
                // No need to cycle through all the rows, remove each one, and force animation.
            } .animation(.easeOut(duration: 0.75), value: newGame)
        }
    }
}